What are the instructions that can implement looping in php?

PHP has three instructions to implement loops: 1) for loop; 2) while loop; 3) do...while loop.

Instructions to implement loops in PHP

There are three main instructions to implement loops in PHP:

• for loop

<code class="php">for ($i = 0; $i < 10; $i++) {
    // 循环体
}</code>

• while loop

<code class="php">while ($condition) {
    // 循环体
}</code>

• do...while loop

<code class="php">do {
    // 循环体
} while ($condition);</code>

Detailed description:

for loop

for loop Is the most commonly used loop structure, which uses three clauses to define the loop:

• Initialization clause: Set the initial value of the loop variable.
• Conditional clause: Specify when to stop the loop.
• Step clause: Update the loop variable after each iteration.

while loop

The while loop will execute the loop body as long as the specified condition is true. If the condition is false at the beginning of the loop, the body of the loop will not execute.

do...while loop

do...while loop is similar to while loop, but it will execute the loop body at least once, even if the condition is at the beginning of the loop is false.

Usage example:

<code class="php">// for 循环
for ($i = 0; $i < 10; $i++) {
    echo "$i ";
}

// while 循环
$j = 0;
while ($j < 10) {
    echo "$j ";
    $j++;
}

// do...while 循环
$k = 0;
do {
    echo "$k ";
    $k++;
} while ($k < 10);</code>

Output:

<code>0 1 2 3 4 5 6 7 8 9
0 1 2 3 4 5 6 7 8 9
0 1 2 3 4 5 6 7 8 9</code>

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