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The break
statement "jumps out" of a loop.
The continue
statement "jumps over" one iteration in the loop.
The Break Statement
You have already seen the break
statement used in an earlier chapter of this tutorial. It was used to "jump out" of a switch()
statement.
The break
statement can also be used to jump out of a loop
示例
for (let i = 0; i < 10; i++) {
if (i === 3) { break; }
text += "The number is " + i + "<br>";
}
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In the example above, the break
statement ends the loop ("breaks" the loop) when the loop counter (i) is 3.
The Continue Statement
continue
语句在满足指定条件时跳过一次(在循环中)迭代,并继续执行循环中的下一次迭代。
This example skips the value of 3
示例
for (let i = 0; i < 10; i++) {
if (i === 3) { continue; }
text += "The number is " + i + "<br>";
}
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JavaScript Labels
To label JavaScript statements you precede the statements with a label name and a colon
标签
statements
The break
and the continue
statements are the only JavaScript statements that can "jump out of" a code block.
语法
break labelname;
continue labelname;
The continue
statement (with or without a label reference) can only be used to skip one loop iteration.
The break
statement, without a label reference, can only be used to jump out of a loop or a switch.
With a label reference, the break statement can be used to jump out of any code block
示例
const cars = ["BMW", "Volvo", "Saab", "Ford"];
list: {
text += cars[0] + "<br>";
text += cars[1] + "<br>";
break list;
text += cars[2] + "<br>";
text += cars[3] + "<br>";
}
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A code block is a block of code between { and }.