constructor
JavaScript constructor 属性
定义和用法
constructor 属性返回对创建此对象的数组函数的引用。
语法
object.constructor
实例
例子 1
在本例中,我们将展示如何使用 constructor 属性:
<script type="text/javascript"> var test=new Array(); if (test.constructor==Array
) { document.write("This is an Array"); } if (test.constructor==Boolean
) { document.write("This is a Boolean"); } if (test.constructor==Date
) { document.write("This is a Date"); } if (test.constructor==String
) { document.write("This is a String"); } </script>
输出:
This is an Array
例子 2
在本例中,我们将展示如何使用 constructor 属性:
<script type="text/javascript">
function employee(name,job,born)
{
this.name=name;
this.job=job;
this.born=born;
}
var bill=new employee("Bill Gates","Engineer",1985);
document.write(bill.constructor
);
</script>
输出:
function employee(name, jobtitle, born) {this.name = name; this.jobtitle = job; this.born = born;}