120 lines
1.9 KiB
Markdown
120 lines
1.9 KiB
Markdown
---
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title: Learn About Php Loops
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---
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Loops are blocks of code that execute a specified number of times. Using loops reduces the number of lines of code.
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PHP works with 4 different types of loops:
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* While loop
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* Do...while loop
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* For loop
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* Foreach loop
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## While loop
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The `while` loop continues to excecute as long as the specified condition is true.
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`php
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<?php
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while(condition is true)
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{
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execute code;
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}
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?>
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Example:
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```php
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<?php
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$x = 1;
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while($x <= 3)
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{
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echo "x=$x ";
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$x++;
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}
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?>
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```
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```
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Output:
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x=1 x=2 x=3
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```
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## Do...while loop
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In the `do...while` loop the block of code is executed before the condition is checked.
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```php
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<?php
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do {
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execute code;
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} while (condition);
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?>
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```
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Example:
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```php
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<?php
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$x= 1;
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do {
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echo "x=$x ";
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$x++;
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} while ($x < 5);
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?>
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```
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```
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Output:
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x=1 x=2 x=3 x=4
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```
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## For loop
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The `for` loop is used when the number of times the block is to be executed is known in advance.
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```php
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<?php
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for (variable initialisation; test condition; increment)
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{
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execute code;
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}
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?>
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```
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Example:
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```php
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<?php
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for ($x=1 ; $x <= 4 ; $x++)
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{
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echo "x= $x ";
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}
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?>
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```
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```
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Output:
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x=1 x=2 x=3 x=4
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```
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## Foreach loop
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The `foreach` loop helps in traversing through arrays.
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```php
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<?php
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foreach ($array as $value)
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{
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executable code;
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}
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?>
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```
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Example:
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```php
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<?php
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$numbers= array("One", "Two", "Three");
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foreach ($numbers as $value)
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{
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echo "$value ";
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}
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?>
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```
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```
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Output:
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One Two Three |