What are the loop statements in javascript

There are three types of loop statements in JavaScript: for, while and do...while, which are used to repeatedly execute blocks of code. The for loop is used when the number of loops is known, the while loop is used when the number of loops is uncertain, and the do...while loop is used when the loop body needs to be executed at least once.

Loop statements in JavaScript

There are three types of loop statements in JavaScript: for, while and do...while.

for loop

for A loop is used to repeatedly execute a block of code until a specific condition is met. Its syntax is as follows:

<code class="javascript">for (initialization; condition; increment-expression) {
  // 循环体
}</code>

• initialization: Executed once at the beginning of the loop.
• condition: Checked before each iteration. If the condition is true, the loop body is executed; otherwise, the loop ends.
• increment-expression: Executed after each iteration.

while loop

while A loop is another loop structure that repeatedly executes a block of code until a specific condition is met . Its syntax is as follows:

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

• condition: Checked before each iteration. If the condition is true, the loop body is executed; otherwise, the loop ends.

do...while loop

do...while loop is similar to while loop, But it will execute the loop body first and then check the condition. Its syntax is as follows:

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

• condition: Checked after each iteration. If the condition is true, the loop continues; otherwise, the loop ends.

Choose the right loop statement

Each loop statement has its own advantages and disadvantages.

• for Loops are typically used when you know the number of times the loop will execute.
• while Loops are used when you are not sure how many times the loop will execute.
• do...while Loops are used when you want the body of the loop to execute at least once.

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