String

Description

"codeapedia.string.js" prototypes the String class to add every
day functionality and class properties.

Code

/** 
* @projectDescription  String for Javascript Library
*
* @author Ryan Estes  http://www.codeapedia.com
* @version 0.1 
*/

/**
* Determines whether the specified string occurs in
* within this string. 
* @return {Boolean} 
*/
String.prototype.contains = function(pValue)
{
   return this.indexOf(pValue) != -1;
}

/**
* Determines whether the end of this string matches
* the specified string.
* @return {Boolean} 
*/
String.prototype.endsWith = function(pValue,pBlnIgnoreCase)
{
   var strSource = this;
   var strValue = pValue;
   if(pBlnIgnoreCase)
   {
      strSource = strSource.toLowerCase();
      strValue = strValue.toLowerCase();
   }
   return strSource.indexOf(strValue) == 
          (strSource.length - strValue.length);
}

/**
* Inserts a string within this string at the specified index
* @return {String} 
*/
String.prototype.insert = function(pValue,pIndex)
{
   if(pValue == null)
   {
      throw "Argument null exception";
   }
   if(pIndex < 0 || pIndex >= this.length)
   {
      throw "Argument out of range exception";
   }
   if(pIndex == 0)
   {
      return pValue + this;
   }
   else if (pIndex == this.length - 1)
   {
      return this + pValue;
   }
   else
   {
      var strStart = this.substring(0,pIndex);
      var strEnd = this.substring(pIndex,this.length);
      return strStart + pValue + strEnd;
   }
}

/**
* Pads this string on the left with a specified number
* of character strings.
* @return {String} 
*/
String.prototype.padLeft = function(pValue,pCount)
{
   var strLeft = "";
   for(var i = 0; i < pCount; i++)
   {
       strLeft += pValue;
   }
   return strLeft + this;
}

/**
* Pads this string on the right with a specified number
* of character strings.
* @return {String} 
*/
String.prototype.padRight = function(pValue,pCount)
{
   var strRight = "";
   for(var i = 0; i < pCount; i++)
   {
       strRight += pValue;
   }
   return this + strRight;
}

/**
* Removes all carriage returns and new lines from this string
* @return {String} 
*/
String.prototype.removeLines = function() 
{
   return this.replace(/(\n\r|\n|\r)/gm,"");
}

/**
* Determines whether the start of this string matches
* the specified string.
* @return {Boolean} 
*/
String.prototype.startsWith = function(pValue,pBlnIgnoreCase)
{
    var strSource = this;
    var strValue = pValue;
    if(pBlnIgnoreCase)
    {
       strSource = strSource.toLowerCase();
       strValue = strValue.toLowerCase();
    }
    return strSource.indexOf(strValue) == 0;
}

/**
* Removes white space from this string
* @return {String} 
*/
String.prototype.trim = function()
{
    return this.replace(/^\s+|\s+$/g,"");
}

/**
* Removes white space from the start of this string
* @return {String} 
*/
String.prototype.trimLeft = function()
{
    return this.replace(/^\s+/,"");
}

/**
* Removes white space from the end of this string
* @return {String} 
*/
String.prototype.trimRight = function()
{
    return this.replace(/\s+$/,"");
}

var String = 
{   
    /**
    * Determines whether two strings specified are equal 
    * @return {Boolean} 
    */
    compare : function(pStringA,pStringB,pBlnIgnoreCase) {
       var strA = pStringA;
       var strB = pStringB;
       if(pBlnIgnoreCase)
       {
          strA = strA.toLowerCase();
          strB = strB.toLowerCase();
       }
       return strA == strB;
    },
    
    // Empty string
    empty : "",
    
    /**
    * Determines whether the specified string is 
    * null or empty 
    * @return {Boolean} 
    */
    isNullOrEmpty : function (pValue) {
       return  pValue == null ||
               pValue == String.empty;
              
    },
    
    /**
    * Converts the specified string to a floating value.
    * Returns minimum float value if fails.
    * @return {Float} 
    */
    toFloat : function(pValue) {
       var strValue = pValue;
       if(pValue == null || isNaN(pValue))
       {
          strValue = "-3.402823E+38";
       }
       return parseFloat(strValue);
    },
    
    /**
    * Converts the specified string to an integer value.
    * Returns minimum integer value if fails.
    * @return (Int} 
    */
    toInt : function(pValue) {
       var strValue = pValue;
       if(pValue == null || isNaN(pValue))
       {
          strValue = "-2147483648";
       }
       return parseInt(strValue);
    }
}

Examples

Code section below alerts "true".
// demonstrates contains
var str = "ASP.NET";
alert(str.contains("."));

Code section below alerts "true".
// demonstrates endsWith
alert(str.endsWith("NET",true));

Code section below alerts "ASP.NET2.0".
// demonstrates insert
alert(str.insert("2.0",str.length - 1));

Code section below alerts "BeginningASP.NET".
// demonstrates padLeft
alert(str.padLeft("Beginning",1));

Code section below alerts "ASP.NET3.0".
// demonstrates padRight
alert(str.padRight("3.0",1));

Code section below alerts "ASP.NET3.0".
// deomstrates removeLines
alert("\r\n\r\nASP.NET\r3.0".removeLines());

Code section below alerts "false".
// demonstrates startsWith
alert(str.startsWith("asp.net"));

Code section below alerts "4","5","5" respectively.
// demonstrates trim functions
var str = " 2345 ";
alert(str.trim().length);
alert(str.trimLeft().length);
alert(str.trimRight().length);

Code section below alerts "true".
// demonstrates String.empty
alert(" ".trim() == String.empty);

Code section below alerts "true".
// demonstrates String.compare
alert(String.compare("A","a",true));

Code section below alerts "true".
// demonstrates String.isNullOrEmpty
alert(String.isNullOrEmpty(String.empty));

Code section below alerts "-3.402823E+38".
// demonstrates String.toFloat
alert(String.toFloat("ASP"));

Code section below alerts "2".
// demonstrates String.toInt
alert(String.toInt("2.0"));