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, job, born)
- {this.name = name; this.job = job; this.born = born;}