JavaScript do...while statement

　JavaScript Statements and Variable Declarations

do...whileStatement creates a loop that executes the specified statement until the calculation result of the test condition is false.

Condition(condition)Evaluate after executing the statement, resulting in the specified statement being executed at least once.

JavaScript provides the following types of loops:

• for - The loop traverses the code block for several times

• for...in - Traverse the properties of the object

• while - The loop traverses the code block when the specified condition is true

• do...while - The loop executes a code block once and then repeats the loop when the specified condition is true

UsebreakStatement terminates the current loop and usescontinueStatement skips the value in the loop.

Syntax:

do {　
　//Executed statements
}
while (condition);

var n = 0;
do {
　　　document.write("<br>The number is "　+　n);
　　　n++;
}
while (n <　5);

Note:If you want to use aCondition(condition)Variables, please initialize them before the loop, and then increment them within the loop. If you forget to increase the variable, the loop will never end. This will cause your browser to crash.

Browser compatibility

All browsers fully support the do ... while statement:

Parameter value

Technical Details

More Examples

Even if the condition is false, this loop will execute at least once because the code block is executed before the condition test:

var n =　5;
do {
　　　document.write("<br>The number is "　+　n);
　　　n++;
}
while (n <　3);　　//　false

Related References

JavaScript Reference:JavaScript while Statement

JavaScript Reference:JavaScript break Statement

JavaScript Reference:JavaScript continue Declaration

　JavaScript Statements and Variable Declarations