javaScript 中的for...in循环
2012-09-02 09:46
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JavaScript For...In Statement
The for...in statement loops throughthe properties of an object.
打印该对象的所有属性
Syntax
for (variable in object)
{
code to be executed
}
Note: The block ofcode inside of the for...in loop will be executed once for each property.
Example
Looping through the properties of anobject:
<!DOCTYPE html>
<html>
<body>
<p>Click the button to loop through the properties of an object named "person".</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction()
{
var x;
var txt="";
var person={fname:"John",lname:"Doe",age:25};
for (x in person)
{
txt=txt + person[x];
}
document.getElementById("demo").innerHTML=txt;
}
</script>
</body>
</html>
结果：
JohnDoe25
The for...in statement loops throughthe properties of an object.
打印该对象的所有属性
Syntax
for (variable in object)
{
code to be executed
}
Note: The block ofcode inside of the for...in loop will be executed once for each property.
Example
Looping through the properties of anobject:
<!DOCTYPE html>
<html>
<body>
<p>Click the button to loop through the properties of an object named "person".</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction()
{
var x;
var txt="";
var person={fname:"John",lname:"Doe",age:25};
for (x in person)
{
txt=txt + person[x];
}
document.getElementById("demo").innerHTML=txt;
}
</script>
</body>
</html>
结果：
JohnDoe25
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