JavaScript simulates implementing a map in the Java language

JavaScript simulates implementing a map in the Java language

Implementation code:

<! DOCTYPE html>

<meta charset= "UTF-8" >

<script type= "Text/javascript" >

Private

var obj={};//empty object container for key-value pairs

function Map ()

{

Put method

This.put=function (Key,value)

{

obj[key]=value;//bind a key-value pair to a JS object

}

Number of users to use to map the container

This.size=function ()

{

Define a variable for the number of records

var count=0;

for (var attr in obj)

{

count++;

}

return count;

}

To get the value from key

This.get=function (Key)

{

/**

Because if the variable is 0 in JS, it is represented as false in the judged condition (type auto-conversion)

*/

if (obj[key]| | obj[key]===0| | Obj[key]===false)

{

return Obj[key];

}

Else

{

return null;

}

}

Delete based on key

This.remove=function (Key)

{

if (obj[key]| | obj[key]===0| | Obj[key]===false)

{

Delete Obj[key];

}

}

Traversing elements in a map

This.eachmap=function (Fun)

{

for (var attr in obj)

{

Fun (attr,obj[attr]);

}

}

}

Simulating a map in Java

var m=new Map ();

M.put ("1", ' Xu Shouwei ');

M.put ("2", 25);

M.put ("3", true);

M.put ("4", New Date ());

Console.log (M.size ());

Console.log (M.get ("1"));

M.remove ("1");

Console.log (M.get ("1"));

M.eachmap (function (key,value) {

Console.log (key+ ":" +value)

});

</script>

<body>

</body>

JavaScript simulates implementing a map in the Java language