insert before last 2 char in javascript

How would I insert a 开发者_JAVA百科% before the last 2 characters in a word?

For example:

var str = "Because";

Output:

Becau%se

How about

var str = "Because";
var len = str.length;
var x = str.substring(0, len-2) + "%" + str.substring(len-2);

Hope this helps.

Try this

var str = "Because";
var result = str.slice(0, -2) +"%"+str.slice(-2);

Here you go! :)

http://jsfiddle.net/6WNk8/

str.substring(0, str.length - 2) + "%" + str.substring(str.length - 2)

Try using this:

str.substring(0,str.length-2)+"%"+str.substring(str.length-2)

Try

function insert(str, value, position){

   return str.substring(0,str.length-position) + value + str.substring(str.length-position);
}

Alternatively...

var str = "Because",
    chars = str.split('');

chars.splice(-2, 0, '%');
str = chars.join('');

jsFiddle.

Here's a function I wrote for you to do it!

var MyString = "Because";

// Inserts a string into another string at a given point
function InsertString(OriginalString, InsertingString, Position) {
    return OriginalString.substring(0, Position) + InsertingString + OriginalString.substring(Position, OriginalString.length);
}

// You can call this as well if you want it n positions from right
function InsertStringFromRight(OriginalString, InsertingString, CharsFromRight) {
    return InsertString(OriginalString, InsertingString, OriginalString.length - CharsFromRight);
}

// Call the function!
var Test1 = InsertString(MyString , "#", 5);
var Test2 = InsertStringFromRight(MyString , "#", 2);

alert(Test1);
alert(Test2);