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 tag is a block element?
<div> <img> <span><div>Web Programming and Development</div>
Which CSS code displays the text underlined?
font-style: italic; text-decoration: underline; font-weight: 500;h2 {
text-decoration: underline;
}
Click on the JavaScript function that can access other function after a specified time.
insertBefore() setTimeout() querySelector()function someFunction() { alert("CoursesWeb.net"); }
setTimeout("someFunction()", 2000);
Click on the instruction that returns the number of items of a multidimensional array in PHP.
count($array) count($array, 1) strlen()$food =["fruits" =>["banana", "apple"), "veggie" =>["collard", "pea"));
$nr_food = count($food, 1);
echo $nr_food; // 6