js实现C#的StringBuilder效果完整实例

/*  ##################### DO NOT MODIFY THIS HEADER #####################  # Title: StringBuilder Class                    #  # Description: Simulates the C# StringBuilder Class in Javascript. #  # Author: Adam Smith                        #  # Email: ibulwark@hotmail.com                    #  # Date: November 12, 2006                      #  #####################################################################*/// Simulates the C# StringBuilder Class in Javascript.// Parameter["stringToAdd"] - The string to add. StringBuilder = function(stringToAdd){    var h = new Array();  if(stringToAdd){h[0] = stringToAdd;}   this.Append = Append;  this.AppendLine = AppendLine;  this.ToString = ToString;  this.Clear = Clear;  this.Length = Length;  this.Replace = Replace;  this.Remove = Remove;  this.Insert = Insert;  this.GetType = GetType;     // Appends the string representation of a specified object to the end of this instance.  // Parameter["stringToAppend"] - The string to append.   function Append(stringToAppend)  {    h[h.length] = stringToAppend;  }   // Appends the string representation of a specified object to the end of this instance with a carriage return and line feed.  // Parameter["stringToAppend"] - The string to append.   function AppendLine(stringToAppend)  {    h[h.length] = stringToAppend;    h[h.length] = "/r/n";  }   // Converts a StringBuilder to a String.  function ToString()  {    if(!h){ return ""; }    if(h.length<2){ return (h[0])?h[0]:""; }    var a = h.join('');    h = new Array();    h[0] = a;    return a;  }  // Clears the StringBuilder  function Clear()  {    h = new Array();  }  // Gets the StringBuilder Length  function Length()  {    if(!h){return 0;}    if(h.length<2){ return (h[0])?h[0].length:0; }    var a = h.join('');    h = new Array();    h[0] = a;    return a.length;  }  // Replaces all occurrences of a specified character or string in this instance with another specified character or string.  // Parameter["oldValue"] - The string to replace.   // Parameter["newValue"] - The string that replaces oldValue.   // Parameter["caseSensitive"] - True or false for case replace.  // Return Value - A reference to this instance with all instances of oldValue replaced by newValue.  function Replace(oldValue, newValue, caseSensitive)  {    var r = new RegExp(oldValue,(caseSensitive==true)?'g':'gi');    var b = h.join('').replace(r, newValue);    h = new Array();    h[0] = b;    return this;  }  // Removes the specified range of characters from this instance.  // Parameter["startIndex"] - The position where removal begins.   // Parameter["length"] - The number of characters to remove.  // Return Value - A reference to this instance after the excise operation has occurred.  function Remove(startIndex, length)  {        var s = h.join('');    h = new Array();    if(startIndex<1){h[0]=s.substring(length, s.length);}    if(startIndex>s.length){h[0]=s;}    else    {      h[0]=s.substring(0, startIndex);       h[1]=s.substring(startIndex+length, s.length);    }    return this;  }  // Inserts the string representation of a specified object into this instance at a specified character position.  // Parameter["index"] - The position at which to insert.  // Parameter["value"] - The string to insert.   // Return Value - A reference to this instance after the insert operation has occurred.  function Insert(index, value)  {    var s = h.join('');    h = new Array();    if(index<1){h[0]=value; h[1]=s;}    if(index>=s.length){h[0]=s; h[1]=value;}    else    {      h[0]=s.substring(0, index);       h[1]=value;       h[2]=s.substring(index, s.length);    }    return this;  }  // Gets the type  function GetType()  {    return "StringBuilder";  }};