Use js to implement the stringbuilder effect of C ~

/*
##################### Do not modify this header ############## #######
# Title: stringbuilder class #
# Description: simulates the C # stringbuilder class in Javascript .#
# Website: www.codevendor.com #
# Author: Adam Smith #
# Email: ibulwark@hotmail.com #
# Date: November 12,200 6 #
######################################## #############################
*/

// 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
FunctionClear ()
{
H= NewArray ();
}

// 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
FunctionGetType ()
{
Return "Stringbuilder";
}
};