JavaScript implements a simple Map sample introduction to _javascript Tips

Copy Code code as follows:

/*
* Map object, realize map function
*
Interface
* Size () Gets the number of map elements
* IsEmpty () to determine if the map is empty
* Clear () Delete all elements of map
* Put (key, value) to add elements (key, value) to the map
* Remove (key) deletes the element of the specified key, returns true successfully, and returns false
* GET (key) gets the element value value of the specified key, and the failure returns null
* Element (index) Gets the elements of the specified index (using Element.key,element.value to get the key and value), and the failure returns null
* ContainsKey (key) to determine if the map contains the elements of the specified key
* Containsvalue (value) determines whether the map contains elements of the specified value
* VALUES () gets an array of all the value in the map (array)
* KEY () gets an array of all keys in the map (array)
*
Example
* var map = new map ();
*
* Map.put ("key", "value");
* var val = map.get ("key")
* ......
*
*/
function Map () {
this.elements = new Array ();

Get the number of map elements
This.size = function () {
return this.elements.length;
};

To determine if a map is empty
This.isempty = function () {
Return (This.elements.length < 1);
};

Delete all elements of map
This.clear = function () {
this.elements = new Array ();
};

Add an element (key, value) to the map
This.put = function (_key, _value) {
This.elements.push ({
Key: _key,
Value: _value
});
};

Deletes the element of the specified key, returns true successfully, and returns false
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;
};

Deletes the element of the specified value, returns true successfully, and returns false
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;
};

Deletes the element of the specified value, returns true successfully, and returns false
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;
};

Gets the element value value of the specified key, and the failure returns null
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;
};

Gets the element of the specified index (using Element.key,element.value to get the key and value), and the failure returns null
This.element = function (_index) {
if (_index < 0 | | | _index >= this.elements.length) {
return null;
}
return This.elements[_index];
};

Determines whether the map contains elements of the specified key
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;
};

Determines whether the map contains elements of the specified value
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;
};

Determines whether the map contains elements of the specified value
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;
};

Gets an array of all the value in the map (array)
This.values = function () {
var arr = new Array ();
for (i = 0; i < this.elements.length; i++) {
Arr.push (This.elements[i].value);
}
return arr;
};

Gets an array of all the value in the map (array)
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;
};

Gets an array of all keys in the map (array)
This.keys = function () {
var arr = new Array ();
for (i = 0; i < this.elements.length; i++) {
Arr.push (This.elements[i].key);
}
return arr;
};

Gets the 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;
};

Gets an array of all keys in the map (array)
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;
};
}