JavaScript DHTML/Language Basics/Switch

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Another switch Statement

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<HTML> <HEAD> <TITLE>Using the switch Statement</TITLE> </HEAD> <BODY> <SCRIPT LANGUAGE="JavaScript"> </SCRIPT> </BODY> </HTML>


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Switch based on integer value

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<HTML> <BODY>

<SCRIPT> var n = 1; switch (n) { case 1: { document.write("n equals 1"); break; } case 2:{ document.write("n equals 2"); break; } case 3:{ document.write("n equals 3"); break; } default:{ document.write("No match!"); break; } } </SCRIPT>

</BODY> </HTML>

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Switch statement

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/* Note that Sunday=0, Monday=1, Tuesday=2, etc.*/ <html> <body> <script type="text/javascript"> var d = new Date() theDay=d.getDay() switch (theDay){

 case 5:
   document.write("Finally Friday")
 break
 case 6:
   document.write("Super Saturday")
 break
 case 0:
   document.write("Sleepy Sunday")
 break
 default:
   document.write("Not weekend!")

} </script>

</body> </html>



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Switch with string value

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<html> <head> <title></title> </head> <body> <script type="text/javascript"> var inputName = prompt("Please enter your name:"); switch(inputName) {

   case "Tom":
       document.write("Welcome " + inputName);
       break;
   case "Name":
       document.write("Name");
       break;
   default:
       document.write("default:" + inputName);

} </script> </body> </html>

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The switch Construction in Action

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/* JavaScript Bible, Fourth Edition by Danny Goodman John Wiley & Sons CopyRight 2001

  • /

<HTML> <HEAD> <TITLE>Switch Statement and Labeled Break</TITLE> <SCRIPT LANGUAGE="JavaScript1.2"> // build two product arrays, simulating two database tables function product(name, price) {

   this.name = name
   this.price = price

} var ICs = new Array() ICs[0] = new product("Septium 900MHz","$149") ICs[1] = new product("Septium Pro 1.0GHz","$249") ICs[2] = new product("Octium BFD 750MHz","$329") var snacks = new Array snacks[0] = new product("Rays Potato Chips","$1.79") snacks[1] = new product("Cheezey-ettes","$1.59") snacks[2] = new product("Tortilla Flats","$2.29") // lookup in the "table" associated with the product function getPrice(selector) {

   var chipName = selector.options[selector.selectedIndex].text
   var outField = document.forms[0].cost
   master:
       switch(selector.options[selector.selectedIndex].value) {
           case "ICs":
               for (var i = 0; i < ICs.length; i++) {
                   if (ICs[i].name == chipName) {
                       outField.value = ICs[i].price
                       break master
                   }
               }
               break
           case "snacks":
               for (var i = 0; i < snacks.length; i++) {
                   if (snacks[i].name == chipName) {
                       outField.value = snacks[i].price
                       break master
                   }
               }
               break
           default:
               outField.value = "Not Found"
       }

} </SCRIPT> </HEAD> <BODY> Branching with the switch Statement


Select a chip for lookup in the chip price tables:

<FORM> Chip:<SELECT NAME="chips" onChange="getPrice(this)"> <OPTION> <OPTION VALUE="ICs">Septium 900MHz <OPTION VALUE="ICs">Septium Pro 1.0GHz <OPTION VALUE="ICs">Octium BFD 750MHz <OPTION VALUE="snacks">Rays Potato Chips <OPTION VALUE="snacks">Cheezey-ettes <OPTION VALUE="snacks">Tortilla Flats <OPTION>Poker Chipset </SELECT>  Price:<INPUT TYPE="text" NAME="cost" SIZE=10> </FORM> </BODY> </HTML> </source>

The switch Statement

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<html> <head>

 <title>The switch Statement</title>

</head> <body>

 <script language="JavaScript1.2" type="text/javascript">
 
 </script>

</body> </html>


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Use switch with true false value

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<html> <head> <title>A Simple Page</title> <script language="JavaScript"> var yourchoice; yourchoice = confirm("True of false") switch (yourchoice) {

   case true:
       alert("true!");
       break;
   case false:
       alert("false");
       break;

} </script> </head> <body> </body> </html>


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