JS While Loop Statement

JavaScript While Loop Statement

While Loop statement is a repetitive statement which is executed after evaluating the condition.
If the resulting value is true the the execution is repetead until becomes false.

Syntax:

while (condition){
   If condition is true the the statement is executed
}

Example:

<script type="text/javascript">
<!--
var a = 0;
document.write("Start Loop" + "<br />");
while (a < 5){
  document.write("Variable a : " + a + "<br />");
  a++;
}
document.write("Stop Loop");
//-->
</script>

The result:

Start Loop
Variable a : 0
Variable a : 1
Variable a : 2
Variable a : 3
Variable a : 4
Stop Loop

JavaScript do…while Loop Statement

do…while Loop statement is a repetitive statement that executes the statements and assess the expression.
If the resulting value is true the the execution is repetead until becomes false.

Syntax:

do{
   Statement_1 to be executed;
   Statement_2 to be executed;
   ...
   Statement_n to be executed;
} while (expression);

Example:

<script type="text/javascript">
<!--
var a = 0;
document.write("Start Loop" + "<br />");
do{
   document.write("Variable a : " + a + "<br />");
   a++;
} while (count < 0);
document.write("Stop Loop");
//-->
</script>

The result:

Start Loop
Variable a : 0
Stop Loop