JS in prototype use (array)

Turn from: http://www.cnblogs.com/chiname/articles/216517.html (Invasion and deletion)

/*
* Method: Array.removeat (Index)
* Function: Delete array element.
* Parameter: Index deletes the subscript of the element.
* Return: Modify array on the original array
*/

Array.prototype.removeAt = function (index) {    if (IsNaN (index) | | Index > This.length) {        return false;}    for (var i = 0, n = 0; i < this.length; i++) {        if (this[i]! = This[index]) {            this[n++] = this[i]        }    }
   this.length-= 1}

/*
* Method: Array.remove (obj)
* Function: Delete array element.
* Parameters: The object to be deleted.
* Return: Modify array on the original array
*/

Array.prototype.remove = function (obj) {     if (null = = obj) {         return;}     for (var i = 0, n = 0; i < this.length; i++) {         if (this[i]! = obj) {             this[n++] = this[i];         }     }     This.length-= 1}

/*
* Method: Array.contains (obj)
* Function: Determines whether an element is in an array.
* Parameters: Object to find
* Return: Found to return true, otherwise return false;
*/

Array.prototype.Contains = function (obj) {     if (null = = obj) {         return;}     for (var i = 0, n = 0; i < this.length; i++) {         if (this[i]! = obj) {             return true;         }     }     return false; }

/*
* Method: Array.indexof (obj)
* Function: Searches for the specified object and returns the zero-based index of the first occurrence
* Parameters: Object to find
* Return: Find the index that returns the element in the array, otherwise return-1
*/

Array.prototype.IndexOf = function (obj) {     if (null = = obj) {         return;} {         for (var i = 0, n = 0; i < this.length; i++) {             if (this[i] = = obj) {                 return i;             }}     }     return-1; }

/*
* Method: Array.clear ()
* Function: Empty array element.
* Parameter: None.
* Return: Empty array
*/

Array.prototype.Clear = function () {     this.length = 0;}

/*
* Method: Array.formatstring ()
* Function: Returns the array position.
* Parameter: None.
* Return: string
*/

Array.prototype.formatString = function () {    var str = ';    for (var i = 0; i < this.length; i++) {        if (i = = this.length-1) {            str + = This[i];        } else {            str + = this[i] + '; ';        }    }    return str;};

　　

JS in prototype use (array)