VIỆN QUỐC GIA ĐỊNH CHUẨN VNCH: January 2016

XỬ DỤNG alert, confirm, prompt, if, else if , else and object

ĐỂ VIẾT JS PROGRAM DÙNG TRONG TIỆM BÁN GẠO VÀ ĐƯỜNG

WRITING A JS PROGRAM FOR A SMALL SHOP SELLING RICE AND SUGAR.

var shop = {

greeting :"WELCOME TO : ENRIQUE SHOP" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs",

appreciation :"THANK YOU \n SEE YOU AGAIN !",

rice :"YOU WANT TO BUY RICE ?",

sugar :"YOU WANT TO BUY SUGAR ?",};

alert(shop.greeting);

alert(shop.product);

var ac = confirm(shop.rice);

if(ac== true){var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))};

if(x <= 100){alert("YOU PAY :"+ x*5.25 + "USD");}

else if(x>100){alert("YOU PAY :"+ x*4.00 + "USD");}

//Nếu click cancel thì window confirm dưới đây xuất hiện.

else{confirm(shop.sugar)};

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

if(y<=10){alert("YOU PAY :"+ y*3.25 + "USD")}

else{alert("YOU PAY :"+ y*3.00 + "USD")}

alert(shop.appreciation);

Ghi chú hướng dẫn.
Program trên đơn giản, còn thiếu hóa đơn.

CHỌN PROGRAM NẦY CÓ HÓA ĐƠN.

Khi viết program nầy, quý bạn sẽ gặp vấn đề có hơi phức tạp vì có 4 giá bán khác nhau chia làm 2 nhóm.

Nhóm bán sỉ có giá thấp và nhóm bán lẻ có giá cao hơn .

Trong mỗi nhóm có 2 giá bán khác nhau là sỉ goị wholesale và lẻ goị la retail cho nên phải suy nghĩ và trắc nghiệm nhiều lần mới thành công.

Ngoài ra cần cắt bỏ những codes không cần thiết để program được ngắn gọn.

Nên xử dụng document.write để những con số không biến mất giúp chúng ta kiểm sóat không bị nhầm lẫn khi tính tiền với khách hàng.

Trong program nầy,nếu muốn chúng ta có thể viết them tên của shop và ngày giờ bán hàng.

Dưới đây là JavaScript Program theo kiến thức của người viết.

Quý bạn thông minh hơn có thể nghĩ cách viết tốt hơn.

------------------------------

var shop = {

greeting :"WELCOME TO : ENRIQUE SHOP" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs",

appreciation :"THANK YOU \n SEE YOU AGAIN !",};

alert(shop.greeting);

alert(shop.product);

var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))

var pay1 = parseFloat(x*5.25);

var pay2 = parseInt(x*4.00);

if(x>=100){document.write("YOU PAY : "+ pay2 +"\n");}

else{document.write("YOU PAY : "+ pay1 +"\n");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write("YOU PAY : "+ pay4);}

else{document.write("YOU PAY :"+ pay3);}

var total1 = pay2+pay4;// wholesale

var total2 = pay1+pay3; //retail

var total3 = pay1+pay4; //retail plus wholesale

var total4 = pay2+pay3; // wholesale plus retail

//here is the sale receipt

alert("TOTAL RICE BAGS IS : "+ x +"\n"+

"TOTAL SUGAR BAGS IS : " +y +"\n"+

"TOTAL PAY IS :" + "\n"+

"* WH :"+ total1 +"\n"+

"* RETAIL :"+ total2 +"\n"+

"* RETAIL PLUS WH :" + total3 +"\n"+

"* WH PLUS RETAIL :" + total4 + "\n"+

shop.appreciation);

Đây là Hoá Đơn mua 150 rice bags và 80 sugar bags.

Quan sát receipt,chúng ta chú ý món nào thì lọt vào mua retail và món nào thì xếp vào wholesale.Theo quy định của chủ cữa hàng nếu mua trên 100 bags áp dụng cho rice và sugar thì xếp vào wholesale.Đó là lý do chúng ta cần phải dùng document.write để có những con số chắc chắn dùng so sánh với số tiền trên receipt.

CHỈNH LẠI NHƯ SAU ĐỂ CÓ RECEIPT RÕ RÀNG HƠN.

if(x>=100){document.write("PAY WHOLESALE RICE : "+ pay2 + "\n");}

else{document.write("PAY RETAIL RICE : "+ pay1 + "\n");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write("/ PAY WHOLESALE SUGAR : "+ pay4);}

else{document.write(" / PAY RETAIL SUGAR : "+ pay3);}

PAY WHOLESALE RICE : 600 / PAY RETAIL SUGAR : 260

Nếu cần in receipt thì dùng document.write thay thế cho alert.

document.write("TOTAL RICE BAGS IS : "+ x +"\n"+
"TOTAL SUGAR BAGS IS : " +y +"\n"+
"TOTAL PAY IS :" + "\n"+
"* WHOLESALE :"+ total1 +"\n"+
"* RETAIL :"+ total2 +"\n"+
"* RETAIL PLUS WHOLESALE :" + total3 +"\n"+
"* WHOLESALE PLUS RETAIL :" + total4 + "\n"+

shop.appreciation);

PAY WHOLESALE RICE : 600 / PAY RETAIL SUGAR : 260 TOTAL RICE BAGS IS : 150 TOTAL SUGAR BAGS IS : 80 TOTAL PAY IS : * WHOLESALE :840 * RETAIL :1047.5 * RETAIL PLUS WHOLESALE :1027.5 * WHOLESALE PLUS RETAIL :860 THANK YOU SEE YOU AGAIN !
Quan sát receipt,chúng ta thấy có những con số không cần thiết.Làm cách nào để loại bỏ những con số màu đỏ vô ích đó?Tại sao có những con số đó?
Chắc quý bạn biết cách thực hiện như ý muốn?
Chắc Quý Bạn say mê JavaScript phải hông ?

Giải thích những con số không cần thiết nhưng vẫn giúp ích khi cần.

1-Mua 10 rice bags và 20 sugar bags.

PAY RETAIL RICE : 52.5 / PAY RETAIL SUGAR : 65

TOTAL RICE BAGS IS : 10

TOTAL SUGAR BAGS IS : 20

TOTAL PAY IS :

* WHOLESALE :100 = 10*4.00 $ +20*3.00$

* RETAIL :117.5 = 10*5.25$ +20*3.25$

* RETAIL PLUS WHOLESALE :112.5 =10*5.25$ +20*3.00$

* WHOLESALE PLUS RETAIL :105 = 10*4.00$ + 20*3.25

THANK YOU

SEE YOU AGAIN !

2- Mua 100 rice bags và 100 sugar bags

PAY WHOLESALE RICE : 400 USD / PAY WHOLESALE SUGAR : 300 USD

TOTAL RICE BAGS IS : 100 TOTAL SUGAR BAGS IS : 100

TOTAL PAY IS :

* WHOLESALE : 700 = 100*4.00$ +100*3.00$

* RETAIL : 850 = 100*5.25$ + 100*3.25$

* RETAIL PLUS WHOLESALE : 825 =100*5.25$ +100*3.00$

* WHOLESALE PLUS RETAIL : 725 = 100*4.00+100*3.25$

THANK YOU

SEE YOU AGAIN !

3-Mua 150 rice bags và 80 sugar bags.

PAY WHOLESALE RICE : 600 USD / PAY RETAIL SUGAR : 260 USD

TOTAL RICE BAGS IS : 150

TOTAL SUGAR BAGS IS : 80

TOTAL PAY IS :

* WHOLESALE : 840 =150*4.00$ + 80*3.00 $

* RETAIL :1047.5 = 150* 5.25$ + 80*3.25$

* RETAIL PLUS WHOLESALE :1027.5 = 150*5.25$ + 80*3.00$

* WHOLESALE PLUS RETAIL :860 = 150*4.00$ + 80*3..25$

THANK YOU

SEE YOU AGAIN !

4- Không mua sugar thi viết ZERO

PAY WHOLESALE RICE : 600 USD / PAY RETAIL SUGAR : 0 USD TOTAL RICE BAGS IS : 150

TOTAL SUGAR BAGS IS : 0

TOTAL PAY IS :

* WHOLESALE :600

* RETAIL : 787.5

* RETAIL PLUS WHOLESALE :787.5 = 150* 5.25$

* WHOLESALE PLUS RETAIL : 600 = 150*4.00$

THANK YOU

SEE YOU AGAIN !

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JAVASCRIPT PROGRAMMING LÀ PHƯƠNG TIỆN TUYỆT VỜI DÙNG ĐỂ DIỄN TẢ SỰ SUY NGHĨ VÀ TÍNH TOÁN CỦA CHÚNG TA.

HOAN HÔ QUÝ BẠN ĐANG SAY MÊ NÓ.

------------------------

SAU KHI DỰ THẢO XONG THẤY PROGRAM ĐÃ HOẠT ĐỘNG ĐƯỢC RỒI,

chúng ta suy nghĩ chỉnh lại program cho gọn va trông đẹp mắt .

Thí dụ program trên được chỉnh lại như sau.Nếu cần in receipt thì viết thêm trong program một function display().

* PAY WHOLESALE RICE : 600 USD * PAY RETAIL SUGAR : 260 USD * RICE BAGS : 150 * SUGAR BAGS : 80
CLICK TO GET RECEIPT

-------------------

var shop = {

greeting :"WELCOME TO : ENRIQUE SHOP \n" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs",

appreciation :"THANK YOU \n SEE YOU AGAIN !",};

alert(shop.greeting);

alert(shop.product);

var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))

var pay1 = parseFloat(x*5.25);

var pay2 = parseInt(x*4.00);

if(x>=100){document.write(" * PAY WHOLESALE RICE : "+ pay2 + " " + "USD");}

else{document.write(" *PAY RETAIL RICE : "+ pay1 + " " + "USD");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write(" * PAY WHOLESALE SUGAR : "+ pay4 +" " + "USD");}

else{document.write(" * PAY RETAIL SUGAR : "+ pay3 + " " + "USD");}

document.write(" * RICE BAGS : " + x + " "+ " * SUGAR BAGS : " + y +" ")

var total1 = pay2+pay4; // wholesale

var total2 = pay1+pay3; //retail

var total3 = pay1+pay4; //retail plus wholesale

var total4 = pay2+pay3; // wholesale plus retail

function display(){

alert(shop.greeting +

"TOTAL RICE BAGS IS : "+ x +"\n"+

"TOTAL SUGAR BAGS IS : " +y +"\n"+

"TOTAL PAY IS :" + "\n"+

"* WHOLESALE :"+ total1 +"\n"+

"* RETAIL :"+ total2 +"\n"+

"* RETAIL PLUS WHOLESALE :" + total3 +"\n"+

"* WHOLESALE PLUS RETAIL :" + total4 + "\n"+

shop.appreciation + "\n"+

"* MANAGER : BAXAO XAOKE "); }

Đây là Hóa Đơn đã cải tiến nhưng vẫn còn cải tiến
nữa theo ý muốn của Manager BaXao Xaoke người Mỹ gốc Mít.

Manager Baxao Xaoke người Mỹ gốc Mít Tố Nữ Lái Thiêu muốn có output giống như sau .

PAY WHOLESALE RICE : 600 USD
* PAY RETAIL SUGAR : 260 USD
* RICE BAGS : 150
* SUGAR BAGS : 80
CLICK TO GET RECEIPT

Click xong thì xuất hiện receipt nầy.Phần trên biến mất.

WELCOME TO : ENRIQUE SHOP
TOTAL RICE BAGS IS : 150
TOTAL SUGAR BAGS IS : 80
TOTAL PAY IS :
* WHOLESALE :840
* RETAIL :1047.5
* RETAIL PLUS WHOLESALE :1027.5
* WHOLESALE PLUS RETAIL :860
THANK YOU SEE YOU AGAIN !
* MANAGER : BAXAO XAOKE

Do yêu cầu trên, chúng ta phải viết lại như sau .Vì phải xử dụng document.write thay alert nên khi viết xuống hàng chúng ta phải huỷ bỏ dấu “\n” đã dùng cho alert rồi thay vào đó dấu “ ”

if(x>=100){document.write(" * PAY WHOLESALE RICE : "+ pay2 + " " + "USD"+ " ");}

else{document.write(" *PAY RETAIL RICE : "+ pay1 + " " + "USD"+" ");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write(" * PAY WHOLESALE SUGAR : "+ pay4 +" " + "USD"+" ");}

else{document.write(" * PAY RETAIL SUGAR : "+ pay3 + " " + "USD"+" ");}

document.write(" * RICE BAGS : " + x + " "+ " * SUGAR BAGS : " + y")

function display(){

document.write(shop.greeting + " "+

"TOTAL RICE BAGS IS : "+ x +" "+

"TOTAL SUGAR BAGS IS : " +y +" " +

"TOTAL PAY IS :" + " "+

"* WHOLESALE :"+ total1 +" "+

"* RETAIL :"+ total2 +" "+

"* RETAIL PLUS WHOLESALE :" + total3 +" "+

"* WHOLESALE PLUS RETAIL :" + total4 + " "+

shop.appreciation + " "+

"* MANAGER : BAXAO XAOKE "); }

Hóa đơn nầy còn thiếu giờ, ngaỳ, tháng và năm

Muốn thỏa mãn yêu cầu của manager người nữ Gốc Mít Lái Thiêu rất dễ thương thì phải viết thêm codes nầy vào trong function display() của program.

var today = new Date();

var day = today.getDate();

var month = today.getMonth()+1; //January is 0!

var year = today.getFullYear();

document.write("* YEAR : " + year + " / " + "MONTH : " + month + " "+ "DAY : " + today)

Cuối cùng sau đây là JavaScript Program mà manager chấp nhận vì có đầy đủ theo mong muốn nên rất cám ơn người viết miễn phí.

var shop = {

greeting :"WELCOME TO : ENRIQUE SHOP \n" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs",

appreciation :"THANK YOU \n SEE YOU AGAIN !",

};

alert(shop.greeting);

alert(shop.product);

alert("YOU MUST PUT ZERO IF YOU DO NOT WANT TO BUY ANY OF THEM");

var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))

var pay1 = parseFloat(x*5.25);

var pay2 = parseInt(x*4.00);

if(x>=100){document.write(" * PAY WHOLESALE RICE : "+ pay2 + " " + "USD"+ " ");}

else{document.write(" *PAY RETAIL RICE : "+ pay1 + " " + "USD"+" ");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write(" * PAY WHOLESALE SUGAR : "+ pay4 +" " + "USD"+" ");}

else{document.write(" * PAY RETAIL SUGAR : "+ pay3 + " " + "USD"+" ");}

document.write(" * RICE BAGS : " + x + " "+ " * SUGAR BAGS : " + y )

var total1 = pay2+pay4; // wholesale

var total2 = pay1+pay3; //retail

var total3 = pay1+pay4; //retail plus wholesale

var total4 = pay2+pay3; // wholesale plus retail

function display(){

document.write(shop.greeting + " "+

"TOTAL RICE BAGS IS : "+ x +" "+

"TOTAL SUGAR BAGS IS : " +y +" " +

"TOTAL PAY IS :" + " "+

"* WHOLESALE :"+ total1 +" "+

"* RETAIL :"+ total2 +" "+

"* RETAIL PLUS WHOLESALE :" + total3 +" "+

"* WHOLESALE PLUS RETAIL :" + total4 + " "+

shop.appreciation + " "+

"* MANAGER : BAXAO XAOKE "+ " ");

//Đây là codes for year,month and day

var today = new Date();

var day = today.getDate();

var month = today.getMonth()+1; //January is 0!

var year = today.getFullYear();

document.write("* YEAR : " + year + " / " + "MONTH : " + month + " "+ "DAY : " + today)}

***************************

CẦU CHÚC QUÝ BẠN THỰC TẬP THÀNH CÔNG
updated Jan-15-2016.
Manager yêu cầu chúng ta loại bỏ những con số không cần thiết rồi thêm vào vài món hàng nưa với giá bán lẻ retail .Chắc quý bạn làm được ?

Không dùng function,viết lại program trên như sau.Những món hàng khác của manager sẽ thêm vaò sau vì rất đơn giản.

var shop = {

greeting :"WELCOME TO : ENRIQUE SHOP " ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

appreciation :"THANK YOU , SEE YOU AGAIN !",};

alert(shop.product +"\n"+ "PLS PUT ZERO IF YOU DO NOT WANT ANY OF THEM");

document.write(shop.greeting + " ")

var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))

var pay1 = parseFloat(x*5.25);

var pay2 = parseInt(x*4.00);

if(x>=100){document.write(" * PAY WHOLESALE RICE : "+ pay2 + " " + "USD"+ " ");}

else{document.write(" *PAY RETAIL RICE : "+ pay1 + " " + "USD"+" ");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write(" * PAY WHOLESALE SUGAR : "+ pay4 +" " + "USD"+" ");}

else{document.write(" * PAY RETAIL SUGAR : "+ pay3 + " " + "USD"+" ");}

document.write(" * RICE BAGS : " + x + " "+

" * SUGAR BAGS : " + y + " "+

shop.appreciation + " "+

"* MANAGER : BAXAO XAOKE "+ " ")

var today = new Date();

var day = today.getDate();

var month = today.getMonth()+1; //January is 0!

var year = today.getFullYear();

document.write("* YEAR : " + year + " / " + "MONTH : " + month + " "+ "DAY : " + today)

SẼ CÓ HÓA ĐƠN NHƯ THẾ NÂY.

WELCOME TO : ENRIQUE SHOP
* PAY WHOLESALE RICE : 600 USD
* PAY RETAIL SUGAR : 260 USD
* RICE BAGS : 150
* SUGAR BAGS : 80
THANK YOU , SEE YOU AGAIN !
* MANAGER : BAXAO XAOKE
* YEAR : 2016 / MONTH : 1
DAY : Fri Jan 15 2016 11:29:44 GMT-0800 (Pacific Standard Time)

Nhưng hóa đơn thiếu tổng cộng số tiền phải trả là 860 USD. Phải nghĩ lại cách viết khác? Vận dụng những gì đã học rồi tiếp tục viết dự thảo.Bỏ bớt document.write

VIẾT TRONG SCRIPT TAGS PHẦN NẦY.

var shop = {

greeting :" WELCOME TO : ENRIQUE SHOP" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

appreciation :"THANK YOU , SEE YOU AGAIN ! ",};

alert(shop.product +"\n"+ "PLS PUT ZERO IF YOU DO NOT WANT ANY OF THEM");

document.write(shop.greeting + " ")

var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))

var pay1 = parseFloat(x*5.25);

var pay2 = parseInt(x*4.00);

if(x>=100){document.write(" * PAY WHOLESALE RICE : "+ pay2 + " " + "USD"+ " ");}

else{document.write(" *PAY RETAIL RICE : "+ pay1 + " " + "USD"+" ");}

var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"));

var pay3 = parseFloat(y*3.25);

var pay4 = parseInt(y*3.00);

if(y>=100){document.write(" * PAY WHOLESALE SUGAR : "+ pay4 +" " + "USD"+" ");}

else{document.write(" * PAY RETAIL SUGAR : "+ pay3 + " " + "USD"+" ");}

var today = new Date();

var day = today.getDate();

var month = today.getMonth()+1; //January is 0!

var year = today.getFullYear();

document.write(" * RICE BAGS : " + x + " "+

" * SUGAR BAGS : " + y + " "+

" * YEAR :" + year + " , " + "MONTH : " + month + " "+

" * DAY : " + today)

function total(){

var r = document.getElementById("rice").value;

var s = document.getElementById("sugar").value;

var T = parseFloat(r) + parseFloat(s);

document.getElementById("demo").innerHTML = ("*TOTAL PAY IS : "+ T + "USD"+" " + " * MANAGER : BAXAO XAOKE "+ " "+ shop.appreciation)}

VIẾT TRONG BODY TAGS PHẦN NẦY.

* PAY FOR RICE:

* PAY FOR SUGAR:

CLICK TO GET TOTAL PAY

SẼ CÓ OUTPUT NHƯ SAU.

WELCOME TO : ENRIQUE SHOP
* PAY WHOLESALE RICE : 600 USD
* PAY RETAIL SUGAR : 260 USD
* RICE BAGS : 150
* SUGAR BAGS : 80
* YEAR :2016 , MONTH : 1
* DAY : Sun Jan 17 2016 07:50:23 GMT-0800 (Pacific Standard Time)
* PAY FOR RICE:
* PAY FOR SUGAR:

*TOTAL PAY IS : 860USD
* MANAGER : BAXAO XAOKE
THANK YOU , SEE YOU AGAIN !

updated Jan/22/16

Manager BAXAO XAOKE CHỌN PROGRAM NẦY VÌ

 ĐƠN GIẢN, RÕ RÀNG VÀ DỄ NHỚ.

         var shop = {

          greeting :" <span style='color:red'>WELCOME TO : ENRIQUE SHOP</span>" ,

          product :"CHÚNG TÔI BÁN RICE VÀ SUGAR \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

          appreciation :"<span style='color:red'>THANK YOU , SEE YOU AGAIN ! </span>",

          rice :"WOULD YOU WANT TO BUY RICE?",

          sugar:"WOULD YOU WANT TO BUY SUGAR?",};

          document.write(shop.greeting +"<br>");

          alert(shop.product +"\n"+ "PLS PUT ZERO IF YOU DO NOT WANT ANY OF THEM");

          var ac1 = confirm(shop.rice);

          if(ac1== true){var x = parseInt(prompt("HOW MANY RICE BAGS YOU WANT?"))};

          var pay1 = parseFloat(x*5.25);

          if(x<100){document.write("YOU PAY FOR RETAIL RICE :"+pay1+" "+"USD"+"<br>")};

          var pay2 = parseInt(x*4.00);

          if(x>=100){document.write("YOU PAY FOR WHOLESALE RICE :"+pay2+" "+"USD"+"<br>")};

          var ac2 = confirm(shop.sugar);

          if(ac2== true){var y = parseInt(prompt("HOW MANY SUGAR BAGS YOU WANT?"))};

          var pay3 = parseFloat(y*3.25);

          if(y<100){document.write("YOU PAY RETAIL SUGAR :"+ pay3 +" "+ "USD"+ "<br>")};

          var pay4 = parseInt(y*3.00);

          if(y>=100){document.write("YOU PAY FOR WHOLESALE SUGAR:"+ pay4 +" "+ "USD"+ "<br>")};

               //  rice pay is considered the start point.

          var T1 = pay2+pay4;// wholesale rice plus wholesale sugar

          var T2 = pay1+pay3; //retail rice plus retail sugar

          var T3 = pay1+pay4;  //retail rice plus wholesale sugar

          var T4 = pay2+pay3;   // wholesale rice plus retail sugar

              var today = new Date();

              var day = today.getDate();

              var month = today.getMonth()+1; //January is 0!

              var year = today.getFullYear();

       document.write("1- RICE BAGS  : " + x + "<br>"+

                      "2- SUGAR BAGS : " + y + "<br>"+

                      "* WHOLESALE RICE PLUS WHOLESALE SUGAR : " + T1 +" "+ "USD"+ "<br>"+

                      "* RETAIL RICE PLUS RETAIL SUGAR : " + T2 +" "+ "USD"+ "<br>"+

                      "* RETAIL RICE PLUS WHOLESALE SUGAR : " + T3 +" "+ "USD"+ "<br>"+

                      "* WHOLESALE RICE PLUS RETAIL SUGAR : " + T4 +" "+ "USD"+ "<br>"+

                         shop.appreciation + "<br>"+

                      "* MANAGER : BAXAO XAOKE "+"<br>"+

                      "* YEAR :" + year + " , " + "MONTH : " + month + "<br>"+

                      "* DAY : " + today);

OUTPUT LÀ RECEIPT NHƯ SAU.

WELCOME TO : ENRIQUE SHOP

YOU PAY FOR WHOLESALE RICE :600 USD

YOU PAY RETAIL SUGAR :260 USD

1- RICE BAGS : 150

2- SUGAR BAGS : 80

* WHOLESALE RICE PLUS WHOLESALE SUGAR : 840 USD

* RETAIL RICE PLUS RETAIL SUGAR : 1047.5 USD

* RETAIL RICE PLUS WHOLESALE SUGAR : 1027.5 USD

* WHOLESALE RICE PLUS RETAIL SUGAR : 860 USD

THANK YOU , SEE YOU AGAIN ! 

3- MANAGER : BAXAO XAOKE 

* YEAR :2016 , MONTH : 1

* DAY : Fri Jan 22 2016 12:43:32 GMT-0800 (Pacific Standard Time)

NHƯNG ĐÂY LÀ PROGRAM ĐÃ ĐƯỢC CẢI TIẾN PHÙ HỢP VỚI SỰ MONG MUỐN CỦA NGƯỜI VIẾT PROGRAM.

MONG MUỐN BỎ NHỮNG CON SỐ KHÔNG CẦN, MUỐN CÓ TOTAL PAY VÀ SỐ LƯỢNG MUA ĐI KÈM THEO TIỀN MUA SỐ LƯƠNG ĐÓ.

QUÝ BẠN THẤY RỎ CHÚNG TA ĐÃ ĐI TỪNG BƯỚC TỪ ĐƠN GIẢN TỚI PHỨC TẠP.

         var shop = {

          greeting :" <span style='color:red'>WELCOME TO : ENRIQUE SHOP</span>" ,

          product :"CHÚNG TÔI BÁN RICE VÀ SUGAR VỚI GIÁ SỈ VÀ LẺ \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

          appreciation :"<span style='color:red'>THANK YOU , SEE YOU AGAIN ! </span>",

          rice :"WOULD YOU WANT TO BUY RICE?",

          sugar:"WOULD YOU WANT TO BUY SUGAR?",}

          document.write(shop.greeting +"<br>");

          alert(shop.product);

          alert("IF YOU DO NOT WANT ANY,PLS CLICK OK \n THEN PUT ZERO IN LATER \n DO NOT CLICK CANCEL");Lý do phải có con số kể cả zero thì TOTAL PAY mới cho kết quả.

          var yes1 = confirm("DO YOU WANT TO BUY OVER 100 RICE BAGS?");

          if(yes1 == true){var x1=prompt("HOW MANY WHOLESALE RICE BAGS YOU WANT?")};

          var pay1 = parseInt(x1*4.00);

          document.write( " * PAY WHOLESALE RICE : "+x1+" "+" bags" +" "+ pay1 + " " + "USD" +"<br>");

          if(yes1==false){x1=0;pay1=0}  // phải có mới tổng cộng được

          var yes2 = confirm("DO YOU WANT TO BUY RETAIL RICE BAGS?");

          if(yes2==true){var x2=prompt("HOW MANY RETAIL RICE BAGS YOU WANT?")};

          var pay2 = parseFloat(x2*5.25);

          document.write( " * PAY RETAIL RICE : "+x2+" "+"bags" +" "+ pay2 + " " + "USD" +"<br>");

          if(yes2=false){x2=0;pay2=0} // phải có mới tổng cộng được

          var yes3 = confirm("DO YOU WANT TO BUY OVER 100 SUGAR BAGS?");

          if(yes3 == true){var y1= prompt("HOW MANY WHOLESALE SUGAR BAGS YOU WANT?")};

          var pay3 = parseInt(y1*3.00);

          document.write( " * PAY WHOLESALE SUGAR : " + y1 +" "+" bags" +" "+ pay3 + " " + "USD" +"<br>");

          if(yes3==false){y1=0;pay3=0}  // phải có mới tổng cộng được

          var yes4 = confirm("DO YOU WANT TO BUY RETAIL SUGAR BAGS?");

          if(yes4=true){var y2=prompt("HOW MANY RETAIL SUGAR BAGS YOU WANT?")};

          var pay4 = parseFloat(y2*3.25);

          document.write( " * PAY RETAIL SUGAR : " + y2 +" "+" bags" +" "+ pay4 + " " + "USD" +"<br>");

          if(yes4==false){y2=0;pay4=0} // phải có mới tổng cộng được

              var T = pay1+pay2+pay3+pay4;

              var today = new Date();

              var day = today.getDate();

              var month = today.getMonth()+1; //January is 0!

              var year = today.getFullYear();

       document.write("* <span style='color:blue'>TOTAL PAY : </span>" + T +" "+ "USD"+ "<br>"+

                         shop.appreciation + "<br>"+

                      "* MANAGER : BAXAO XAOKE "+"<br>"+

                      "* YEAR :" + year + " , " + "MONTH : " + month + "<br>"+

                      "* DAY : " + today);

RECEIPT OUTPUT.

WELCOME TO : ENRIQUE SHOP

* PAY WHOLESALE RICE : 150 bags 600 USD

* PAY RETAIL RICE : 0 bags 0 USD

* PAY WHOLESALE SUGAR : 0 bags 0 USD

* PAY RETAIL SUGAR : 80 bags 260 USD

* TOTAL PAY : 860 USD

THANK YOU , SEE YOU AGAIN ! 

* MANAGER : BAXAO XAOKE 

* YEAR :2016 , MONTH : 1

* DAY : Sat Jan 23 2016 09:15:52 GMT-0800 (Pacific Standard Time)



Jan-25-2016
Tiếp tục cải tiến như sau.


PROGRAM NẦY CÓ ƯU ĐIỂM :
* MUỐN MUA SỐ LƯƠNG BAO NHIÊU TUỲ Ý KHÔNG BẮT BUỘC XÁC NHẬN TRƯỚC.
* ĐƠN GIẢN HƠN HẾT.KHÔNG CẦN NHIỀU CODES.
* CHỈ NHÌN VÀO HÀNG CHỮ SẼ THẤY NGAY TỔNG SỐ TIỀN PHẢI TRẢ.
              Quý bạn có thể có cách viết khác tốt hơn.
 

         var shop = {
          greeting :" <span style='color:red'>WELCOME TO : ENRIQUE SHOP</span>" ,
          product :"CHÚNG TÔI BÁN RICE VÀ SUGAR VỚI GIÁ SỈ VÀ LẺ \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",
          appreciation :"<span style='color:red'>THANK YOU , SEE YOU AGAIN ! </span>", }
          
          document.write(shop.greeting +"<br>");  
          alert(shop.product);               
          alert("CHÚNG TÔI BÁN SỈ VÀ BÁN LẺ MUA DƯỚI 100 THÌ TRẢ GIÁ LẺ");
             
             var x= parseInt(prompt('HOW MANY RICE BAGS DO YOU WANT ?'));  //hỏi như vậy nhưng viết vaò con số tuỳ ý.         
             var pay2=parseFloat(x*5.25)
             if(x<100){document.write("YOU PAY retail RICE : " +pay2+ " "+ "USD"+"<br>")}            
             var pay1=parseInt(x*4,00)
             if(x>=100){document.write("YOU PAY WHOLESALE RICE : " +pay1+ " "+ "USD"+"<br>")}
          
             var y= parseInt(prompt('HOW MANY SUGAR BAGS DO YOU WANT ?'));             
             var pay4=parseFloat(y*3.25)
             if(y<100){document.write("YOU PAY retail SUGAR : " +pay4 + " "+ "USD"+"<br>")} 
             var pay3=parseInt(y*3.00)
             if(y>=100){document.write("YOU PAY WHOLESALE SUGAR : " +pay3+ " "+ "USD"+"<br>")}
              
                var T= x+y;//không làm parseInt nữa vì đã làm ở trên parseInt 
                   
                    //  rice pay is considered the start point.
 
                var T1 = pay2+pay4;// wholesale rice plus wholesale sugar
                var T2 = pay1+pay3; //retail rice plus retail sugar 
                var T3 = pay1+pay4;  //retail rice plus wholesale sugar
                var T4 = pay2+pay3;   // wholesale rice plus retail sugar
                                 
              var today = new Date();
              var day = today.getDate();
              var month = today.getMonth()+1; //January is 0!
              var year = today.getFullYear(); 
          
       document.write("1- RICE BAGS  : " + x + "<br>"+
                      "2- SUGAR BAGS : " + y + "<br>"+
                      "* Retail RICE PLUS Retail SUGAR : " + T1 +" "+ "USD"+ "<br>"+
                      "* WHOLESALE RICE PLUS WHOLESALE SUGAR : " + T2 +" "+ "USD"+ "<br>"+ 
                      "* WHOLESALE RICE PLUS Retail SUGAR : " + T3 +" "+ "USD"+ "<br>"+
                      "* Retail RICE PLUS WHOLESALE SUGAR : " + T4 +" "+ "USD"+ "<br>"+                     
                         shop.appreciation + "<br>"+
                      "3- MANAGER : BAXAO XAOKE "+"<br>"+ 
                      "* YEAR :" + year + " , " + "MONTH : " + month + "<br>"+                           
                      "* DAY : " + today); 
 
     
 
 RECEIPT OUTPUT.
WELCOME TO : ENRIQUE SHOP

YOU PAY WHOLESALE RICE : 720 USD

YOU PAY retail SUGAR : 260 USD

1- RICE BAGS : 180

2- SUGAR BAGS : 80

* Retail RICE PLUS Retail SUGAR : 1205 USD

* WHOLESALE RICE PLUS WHOLESALE SUGAR : 960 USD

* WHOLESALE RICE PLUS Retail SUGAR : 980 USD

* Retail RICE PLUS WHOLESALE SUGAR : 1185 USD

THANK YOU , SEE YOU AGAIN ! 

3- MANAGER : BAXAO XAOKE 

* YEAR :2016 , MONTH : 1

* DAY : Mon Jan 25 2016 13:47:17 GMT-0800 (Pacific Standard Time)
    
GHI CHÚ.
Quan sát 2 con số 720 USD và 260 USD thì thấy ngay con số tổng cộng là 980 USD nhờ có câu WHOLESALE RICE PLUS Retail SUGAR

 SO SÁNH 2 PROGRAMS SAU CÙNG,CHÚNG TA THẤY RÕ PROGRAM NAÒ NGẮN GỌN VÀ TIỆN LỢI?

ĐÂY LÀ OUTPUT CỦA 2 HÓA ĐƠN.

WELCOME TO : ENRIQUE SHOP
* PAY WHOLESALE RICE : 150 bags 600 USD
* PAY RETAIL RICE : 0 bags 0 USD
* PAY WHOLESALE SUGAR : 0 bags 0 USD
* PAY RETAIL SUGAR : 80 bags 260 USD
* TOTAL PAY : 860 USD
THANK YOU , SEE YOU AGAIN !
* MANAGER : BAXAO XAOKE
* YEAR :2016 , MONTH : 1
* DAY : Tue Jan 26 2016 05:55:54 GMT-0800 (Pacific Standard Time)

WELCOME TO : ENRIQUE SHOP
YOU PAY WHOLESALE RICE : 600 USD
YOU PAY retail SUGAR : 260 USD
1- RICE BAGS : 150
2- SUGAR BAGS : 80
* Retail RICE PLUS Retail SUGAR : 1047.5 USD
* WHOLESALE RICE PLUS WHOLESALE SUGAR : 840 USD
* WHOLESALE RICE PLUS Retail SUGAR : 860 USD
* Retail RICE PLUS WHOLESALE SUGAR : 1027.5 USD
THANK YOU , SEE YOU AGAIN !
3- MANAGER : BAXAO XAOKE
* YEAR :2016 , MONTH : 1
* DAY : Tue Jan 26 2016 05:56:19 GMT-0800 (Pacific Standard Time)

updated Feb-7-2016

PROGRAM NẦY CÓ TỔNG CỘNG 13 LINES OF CODES.

NGẮN GỌN NHỨT VÀ CÓ THỂ VIẾT THÊM CODES CỦA COFFEE POTS VÀ MILK CANS.

var shop = {

greeting :" WELCOME TO : ENRIQUE SHOP" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR VỚI GIÁ SỈ VÀ LẺ \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

appreciation :"THANK YOU , SEE YOU AGAIN ! ", }

document.write(shop.greeting +" ");

alert(shop.product);

alert("IF YOU DO NOT WANT ANY,PLS PUT ZERO \n THEN CLICK OK \n DO NOT CLICK CANCEL");

var x1=prompt("HOW MANY RICE BAGS YOU WANT?")

var pay1 = parseInt(x1*4.00);

if(x1>100){document.write( " * PAY WHOLESALE RICE : "+x1+" "+" bags" +" "+ pay1 + " " + "USD" +" ")};

var pay2 = parseFloat(x1*5.25);

if(x1<=100){pay1=0;document.write( " *PAY RETAIL RICE : "+x1+" "+"bags" +" "+ pay2 + " " + "USD" +" ")}

var y1= prompt("HOW MANY SUGAR BAGS YOU WANT?");

var pay3 = parseInt(y1*3.00);

if(y1>100){document.write( " * PAY WHOLESALE SUGAR : " + y1 +" "+" bags" +" "+ pay3 + " " + "USD" +" ")};

var pay4 = parseFloat(y1*3.25);

if(y1<=100){pay3=0;document.write( " * PAY RETAIL SUGAR : " + y1 +" "+" bags" +" "+ pay4 + " " + "USD" +" ");}

var caf = parseInt(prompt("HOW MANY COFFEE POTS YOU WANT ?"));

var pay5 = parseFloat(caf*7.50);

document.write("*YOU PAY FOR COFFEE : " + caf + " "+"pots"+ " "+ pay5 +" " + "USD" + " ");

var mk = parseInt(prompt("HOW MANY MILK CANS YOU WANT ?"));

var pay6 = parseFloat(mk*1.75);

document.write("*YOU PAY FOR MILK CANS : " + mk +" "+"cans"+ " "+ pay6 +" " + "USD" + " ");

var T = pay1+pay2+pay3+pay4+pay5+pay6;

var today = new Date();

var day = today.getDate();

var month = today.getMonth()+1; //January is 0!

var year = today.getFullYear();

document.write("* TOTAL PAY : " + T +" "+ "USD"+ " "+

shop.appreciation + " "+

"* MANAGER : BAXAO XAOKE "+" "+

"* YEAR :" + year + " , " + "MONTH : " + month + " "+

"* DAY : " + today);

OUTPUT OF PRORAM .

WELCOME TO : ENRIQUE SHOP
*PAY RETAIL RICE : 1 bags 5.25 USD
* PAY RETAIL SUGAR : 0 bags 0 USD
*YOU PAY FOR COFFEE : 1 pots 7.5 USD
*YOU PAY FOR MILK CANS : 10 cans 17.5 USD
* TOTAL PAY : 30.25 USD
THANK YOU , SEE YOU AGAIN !
* MANAGER : BAXAO XAOKE
* YEAR :2016 , MONTH : 2
* DAY : Sun Feb 07 2016 09:14:58 GMT-0800 (Pacific Standard Time

UPDATED 17-FEB-16
TUỲ THEO SỰ SUY NGHĨ CHÚNG TA CÓ THỂ TÌM RA NHIỀU CÁCH VIẾT KHÁC NHAU.
QUÝ BẠN CÓ THỂ CÓ CÁCH VIẾT TỐT HƠN NỮA.
ĐÂY LÀ PRORAM RẤT DỄ NHỚ,NGẮN GỌN CÓ KÈM THÊM MÁY LÀM TÓAN CỘNG

CHÚNG TA CÓ THỂ CLICK CANCEL,KHÔNG YÊU CẦU SET ZERO NHƯNG PROGRAM VẪN HOẠT ĐỘNG KHÔNG BỊ TRỞ NGẠI.

Viết phần nầy trong script tags.

var shop = {

greeting :" WELCOME TO : ENRIQUE SHOP" ,

product :"CHÚNG TÔI BÁN RICE VÀ SUGAR VỚI GIÁ SỈ VÀ LẺ \n RICE BAG : 5 lbs \n SUGAR BAG : 2 lbs ",

appreciation :"THANK YOU , SEE YOU AGAIN ! ",}

document.write(shop.greeting +" ");

alert(shop.product);

var x1 = prompt("OVER 100 BAGS.\n HOW MANY WHOLESALE RICE BAGS YOU WANT?");

var pay1 = parseInt(x1*4.00);

var a1 = pay1;

var x2 = prompt("LESS THAN 100 BAGS.\n HOW MANY RETAIL RICE BAGS YOU WANT?");

var pay2 = parseFloat(x2*5.25);

var a2 = pay2;

var y1 = prompt("OVER 100 BAGS.\n HOW MANY WHOLESALE SUGAR BAGS YOU WANT?");

var pay3 = parseInt(y1*4.00);

var a3 = pay3;

var y2 = prompt("LESS THAN 100 BAGS.\n HOW MANY RETAIL RICE BAGS YOU WANT?");

var pay4 = parseFloat(y2*3.25);

var a4 = pay4;

var tot = a1+a2+a3+a4;

document.write("* TOTAL PAY : " + tot +" "+ "USD"+ " "+

shop.appreciation + " "+

"* MANAGER : BAXAO XAOKE " + " ");

function findSum(){

document.getElementById("r1").value = a1

document.getElementById("r2").value = a2

document.getElementById("s1").value = a3

document.getElementById("s2").value = a4

document.getElementById("Total").value = tot

}

Viết phần nầy trong body taga

1-RICE WHOLESALE PAY : <input type="text" size ="5" id ="r1" />

2-RICE RETAIL PAY : <input type="text"size ="5" id ="r2" />

3-SUGAR WHOLESALE PAY : <input type="text"size ="5" id ="s1" />

4-SUGAR RETAIL PAY : <input type="text"size ="5" id ="s2" />

TOTAL PAY : <input type="text" size ="5" id="Total"/>

CLICK

OUTPUT RECEIPT OF PROGRAM

WELCOME TO : ENRIQUE SHOP
* TOTAL PAY : 8.5 USD
THANK YOU , SEE YOU AGAIN !
* MANAGER : BAXAO XAOKE

1-RICE WHOLESALE PAY :
2-RICE RETAIL PAY :
3-SUGAR WHOLESALE PAY :
4-SUGAR RETAIL PAY :
TOTAL PAY : CLICK

Để ngăn chận nhầm lẩn khi chọn số lượng cần mua,chúng ta viết thêm vào program những codes như sau.

var pay1 = parseInt(x1*4.00);

if(x1<=100){pay1=0};//viết thêm

var a1 = pay1;

var pay2 = parseFloat(x2*5.25);

if(x2>100){pay2=0}//viết thêm

var a2 = pay2;

var pay3 = parseInt(y1*4.00);

if(y1<=100){pay3=0};//viết thêm

var a3 = pay3;

var pay4 = parseFloat(y2*3.25);

if(y2>100){pay4=0}//viế thêm

var a4 = pay4;

WELCOME TO BLOGGER VQGĐC

Friday, January 1, 2016

WRITING A JS PROGRAM FOR A SMALL SHOP SELLING RICE AND SUGAR.