Simple Map implementation in javascript

Simple Map implementation in javascript

This article describes how to use javascript to implement a simple Map. You can obtain, Judge, delete, and add a map.

The Code is as follows:

/*

* MAP object to implement the MAP function

*

* Interface:

* Size () gets the number of MAP elements

* IsEmpty () determines whether the MAP is empty.

* Clear () deletes all MAP elements.

* Add an element (key, value) to the MAP using put (key, value)

* Remove (key) deletes the element of the specified KEY. If the key is successfully deleted, True is returned. If the KEY is failed, False is returned.

* Get (key) gets the element VALUE of the specified KEY. If the VALUE fails, NULL is returned.

* Element (index) obtains the elements of the specified index (using element. key, element. value to obtain KEY and VALUE). If the element fails, NULL is returned.

* ContainsKey (key) determines whether the MAP contains elements of the specified KEY.

* ContainsValue (value) determines whether the MAP contains the element of the specified VALUE.

* Values () obtains the ARRAY (ARRAY) of all values in the MAP)

* Keys () obtains the ARRAY (ARRAY) of all keys in the MAP)

*

* Example:

* Var map = new Map ();

*

* Map. put ("key", "value ");

* Var val = map. get ("key ")

*......

*

*/

Function Map (){

This. elements = new Array ();

 

// Obtain the number of MAP elements

This. size = function (){

Return this. elements. length;

};

 

// Determine whether the MAP is empty

This. isEmpty = function (){

Return (this. elements. length <1 );

};

 

// Delete All MAP elements

This. clear = function (){

This. elements = new Array ();

};

 

// Add the element (key, value) to the MAP)

This. put = function (_ key, _ value ){

This. elements. push ({

Key: _ key,

Value: _ value

});

};

 

// Delete the element of the specified KEY. If the KEY is successfully deleted, True is returned. If the KEY fails to be deleted, False is returned.

This. removeByKey = function (_ key ){

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. key = _ key ){

This. elements. splice (I, 1 );

Return true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Delete the element of the specified VALUE. If the element is successfully deleted, True is returned. If the element fails, False is returned.

This. removeByValue = function (_ value) {// removeByValueAndKey

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. value = _ value ){

This. elements. splice (I, 1 );

Return true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Delete the element of the specified VALUE. If the element is successfully deleted, True is returned. If the element fails, False is returned.

This. removeByValueAndKey = function (_ key, _ value ){

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. value = _ value & this. elements [I]. key = _ key ){

This. elements. splice (I, 1 );

Return true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Obtain the element VALUE of the specified KEY. If the VALUE fails, NULL is returned.

This. get = function (_ key ){

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. key = _ key ){

Return this. elements [I]. value;

}

}

} Catch (e ){

Return false;

}

Return false;

};

 

// Obtain the elements of the specified index (using element. key, element. value to obtain KEY and VALUE). If the index fails, NULL is returned.

This. element = function (_ index ){

If (_ index <0 | _ index> = this. elements. length ){

Return null;

}

Return this. elements [_ index];

};

 

// Determine whether the MAP contains the specified KEY element.

This. containsKey = function (_ key ){

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. key = _ key ){

Bln = true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Determine whether the MAP contains the specified VALUE element.

This. containsValue = function (_ value ){

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. value = _ value ){

Bln = true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Determine whether the MAP contains the specified VALUE element.

This. containsObj = function (_ key, _ value ){

Var bln = false;

Try {

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. value = _ value & this. elements [I]. key = _ key ){

Bln = true;

}

}

} Catch (e ){

Bln = false;

}

Return bln;

};

 

// Obtain the ARRAY (ARRAY) of all values in the MAP)

This. values = function (){

Var arr = new Array ();

For (I = 0; I <this. elements. length; I ++ ){

Arr. push (this. elements [I]. value );

}

Return arr;

};

 

// Obtain the ARRAY (ARRAY) of all values in the MAP)

This. valuesByKey = function (_ key ){

Var arr = new Array ();

For (I = 0; I <this. elements. length; I ++ ){

If (this. elements [I]. key = _ key ){

Arr. push (this. elements [I]. value );

}

}

Return arr;

};

 

// Obtain the ARRAY (ARRAY) of all keys in the MAP)

This. keys = function (){

Var arr = new Array ();

For (I = 0; I <this. elements. length; I ++ ){

Arr. push (this. elements [I]. key );

}

Return arr;

};

 

// Get key through value

This. keysByValue = function (_ value ){

Var arr = new Array ();

For (I = 0; I <this. elements. length; I ++ ){

If (_ value = this. elements [I]. value ){

Arr. push (this. elements [I]. key );

}

}

Return arr;

};

 

// Obtain the ARRAY (ARRAY) of all keys in the MAP)

This. keysRemoveDuplicate = function (){

Var arr = new Array ();

For (I = 0; I <this. elements. length; I ++ ){

Var flag = true;

For (var j = 0; j <arr. length; j ++ ){

If (arr [j] = this. elements [I]. key ){

Flag = false;

Break;

}

}

If (flag ){

Arr. push (this. elements [I]. key );

}

}

Return arr;

};

}