Summary of Javascript custom type methods_javascript skills

1. Define type

Copy code The code is as follows:

function UserObject (parameter) {
}

parameter can be omitted, which is equivalent to the constructor parameter in C#.
2. Instantiate the custom type

Copy the code The code is as follows:

3. Add attributes

Copy code The code is as follows:

function userobject(parameter){
this.firstproperty=parameter
this.secondproperty=" This is the second property"
}

//Use

to copy the code The code is as follows :

<script> <br>var myobject=new userobject("hi there.") <br>//alerts "hi there." <br>alert(myobject.firstproperty) <br>//writes "This is the second property" <br>document.write(myobject.secondproperty) <br></script>

4. Add method (circle class )

Copy code The code is as follows:

//first method function
function computearea(){
var area=this.radius*this.radius*3.14
return area
}
//second method function
function computediameter(){
var diameter =this.radius*2
return diameter
}

Associated to the custom type:

Copy code The code is as follows:

Use custom method:

Copy code The code is as follows: