Javascript - While Loop
The while loop loops through a block of code while a specified condition is true.
JavaScript While Loop Syntax
while (var<=endvalue)
{
code to be executed
}
Note: The <= could be any comparing statement.
The example below defines a loop that starts with i=0. The loop will continue to run as long as i is less than, or equal to 5. i will increase by 1 each time the loop runs:
JavaScript While Loop Example
<html>
<body>
<script type="text/javascript">
var i=0;
while (i<=5)
{
document.write("The number is " + i);
document.write("<br />");
i++;
}
</script>
</body>
</html>
The do...while loop is a variant of the while loop. This loop will execute the block of code ONCE, and then it will repeat the loop as long as the specified condition is true.
JavaScript Do.. While Loop Syntax
do
{
code to be executed
}
while (var<=endvalue);
The example below uses a do...while loop. The do...while loop will always be executed at least once, even if the condition is false, because the statements are executed before the condition is tested:
JavaScript do.. while Loop Example
<html>
<body>
<script type="text/javascript">
var i=0;
do
{
document.write("The number is " + i);
document.write("<br />");
i++;
}
while (i<=5);
</script>
</body>
</html>
