A while loop just looks at a short comparison and repeats until the comparison is no longer True.

The while() loop

The while() loops executes a code as long as a condition is True. If the condition starts out as false, the statements won’t execute at all.

- Syntax:
while(condition){
 //code to be executed
}
Example:
<script>
var i =0;
while(i<5){
 document.write('<br /> i = '+i);
 i++;
}
</script>
- First it's declared a variable 'i' with the value of 0. The 'while' statement checks the condition (here: i<5), which it's True and permits the execution of block code inside the brackets. The 'i++' increments the value of 'i' and check again the condition. The loop will stop when the 'i' reach 5.

do ... while() loops

The do...while() loop is a variant of the while() loop. First it is executed the block of code, and then it will repeat the loop as long as the specified condition is true.

Syntax:
do {
 //code to be executed
}
while(condition)
Here is a simple example:
<script>
var x = 8;
do {
 document.write('<br> x = '+x);
 x++;
}
while(x<5)
</script>
- This example display 'x = 8'.
As you can notice, although the condition is false (x<5), the code between braces is still executed once.

Daily Test with Code Example

HTML
CSS
JavaScript
PHP-MySQL
Which attribute indicates that an input field must be filled out before submitting?
required="required" autofocus="autofocus" placeholder="text"
<input type="text" name="name1" required="required" />
Which CSS method increases or decreases the size of the HTML element (including its content)?
translate() scale() skew()
#some_id:hover {
  transform: scale(2, 1.5);
  -ms-transform: scale(2, 1.5);    /* IE 9 */
  -moz-transform: scale(2, 1.5);   /* Firefox */
}
Click on the Date object method that returns the day of the month.
setDate() getMonth() getDate()
var rightnow = new Date();
var day = rightnow.getDate();
alert(day);
Which function is used to upload a file on server?
is_file() move_uploaded_file() fopen()
if(move_uploaded_file($_FILES["field_name"]["tmp_name"], "dir/file_name")) {
  echo "The file succesfully uploaded";
}
While loops

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