Showing posts with label Loops. Show all posts
Showing posts with label Loops. Show all posts

The do...while Loop
3:31 AM - Posted by Vipin C - 0 comments
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.

Syntax

do
  {
  code to be executed
  }
while (var<=endvalue);

Example

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:

<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>


The while Loop
3:30 AM - Posted by Vipin C - 0 comments
The while loop loops through a block of code while a specified condition is true.

Syntax

while (var<=endvalue)
  {
  code to be executed
  }
Note: The <= could be any comparing statement.

Example

The example below defines a loop that starts with i=0. The loop will continue to run as long as ii will increase by 1 each time the loop runs: is less than, or equal to 5.

<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 for Loop
3:28 AM - Posted by Vipin C - 0 comments
The for loop is used when you know in advance how many times the script should run.

Syntax

for (var=startvalue;var<=endvalue;var=var+increment)
{
code to be executed
}

Example

The example below defines a loop that starts with i=0. The loop will continue to run as long as ii will increase by 1 each time the loop runs. is less than, or equal to 5.
Note: The increment parameter could also be negative, and the <= could be any comparing statement.

<html>
<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=5;i++)
{
document.write("The number is " + i);
document.write("<br />");
}
</script>
</body>
</html>



JavaScript Loops
3:26 AM - Posted by Vipin C - 0 comments
Often when you write code, you want the same block of code to run over and over again in a row. Instead of adding several almost equal lines in a script we can use loops to perform a task like this.
In JavaScript, there are two different kind of loops:
  • for - loops through a block of code a specified number of times
  • while - loops through a block of code while a specified condition is true