if ("first"==strFL)
Console.WriteLine("The index value returned is : "+ objString.str.IndexOfAny(c,intStart));

else
Console.WriteLine("The index value returned is : "+ objString.str.LastIndexOfAny(c,intStart));

break;
case 3:
Console.Write("Enter the string for the character array :");
strChar=Console.ReadLine();
c=strChar.ToCharArray();
Console.Write("Enter the starting Index for search :");
intStart=int.Parse(Console.ReadLine());
Console.Write("Enter the number of characters to searc :");
intCount=int.Parse(Console.ReadLine());
if ("first"==strFL)
Console.WriteLine("The index value returned is : "+ objString.str.IndexOfAny(c,intStart,intCount));

else
Console.WriteLine("The index value returned is : "+ objString.str.LastIndexOfAny(c,intStart,intCount));

break;
case 4:
blnStay=false;
break;
}
if (blnStay)
mtdIndexAnyImpl(strValue,strFL);
}

private void mtdInsert() {
Console.WriteLine("String.Insert(int index,string str) - > this functions returns the original string with 'str' inserted at 'index'");

Console.WriteLine("the original string : " + objString.str);
Console.Write("Enter the string to be inserted : ");
string strTmp=Console.ReadLine();
Console.Write("Enter the position where it has to be inserted :");
int intTmp=int.Parse(Console.ReadLine());
objString.str=objString.str.Insert(intTmp,strTmp);
Console.WriteLine("the modified string : " + objString.str);
}

private void mtdJoin() {
string[] s={"welcome","to","the","world","of","c#"};
Console.WriteLine("1.String.Join(string str,string[] strarr) - > this functions joins the string arrays using 'str'");

Console.WriteLine("2.String.Join(string str,string[] strarr,int i,int j) - > this functions joins the string arrays using 'str' starting from the 'i' th array element and 'j' number of elements after it. ");

Console.Write("Enter your choice :");
string strChoice=Console.ReadLine();
if ("1"==strChoice) {
Console.WriteLine("The string array is :str[0]='welcome',str[1]='to',str[2]='the',str[3]='world',str[4]='of',str[5]='c#'");

Console.Write("Enter the string with which to join : ");
string strTmp=Console.ReadLine();
Console.WriteLine("The joint string is : " + String.Join(strTmp,s));
}
else {
Console.WriteLine("The string array is :str[0]='welcome',str[1]='to',str[2]='the',str[3]='world',str[4]='of',str[5]='c#'");

Console.Write("Enter the string with which to join : ");
string strTmp=Console.ReadLine();
Console.Write("Enter the starting index of the array : ");
int intStart=int.Parse(Console.ReadLine());
Console.Write("Enter the number of elements to join :" );
int intCount=int.Parse(Console.ReadLine());
Console.WriteLine("The joint string is : " + String.Join(strTmp,s,intStart,intCount));

}
}

private void mtdLastIndex() {
Console.WriteLine("String.LastIndexOf() - > this returns the index of the last occurence of a charcter or string in the given string.");

Console.WriteLine("The search of the string stops when the required value is founds or proceedes until the beginning of the string has been reached");

Console.WriteLine("It returns the index if the value is found or '-1' if not found.");
mtdIndexImpl("LastIndex","last");

}

private void mtdLastIndexAny() {
Console.WriteLine("String.LastIndexOfAny() - > this returns the index of the last occurence of any charcter of the character array in the given string.");

Console.WriteLine("The search of the string stops when the required value is founds or proceedes until the beginning of the string has been reached");

Console.WriteLine("It returns the index if the value is found or '-1' if not found.");
mtdIndexAnyImpl("LastIndex","last");
}

private void mtdLength() {
Console.WriteLine("String.Length - > this property returns the length of the string.");
Console.WriteLine("The length of '"+objString.str+"' is : "+objString.str.Length);
}

private void mtdPadLeft() {
mtdPad("Left");
}

private void mtdPad(String strVal) {
Console.WriteLine("String.Pad"+strVal+"() - > this method pads spaces or some other character to the "+strVal+" of the string");

Console.WriteLine("String.Pad"+strVal+"(int i) -> fills spaces to the "+strVal+" of the string, 'i' specifies the length of the string along with spaces");

Console.WriteLine("String.Pad"+strVal+"(int i,char c) -> fills the character 'c' to the "+strVal+" of the string, 'i' specifies the length of the string along with spaces");

Console.WriteLine("The original string :"+objString.str );
Console.Write("Enter the length of the desired string : ");
int intStart=int.Parse(Console.ReadLine());
Console.Write("Enter the Character to be padded(enter nothing for spaces) :");
string strTmp=Console.ReadLine();
if(!strTmp.Equals("")) {
char c=(strTmp.ToCharArray())[0];
if ("Left"==strVal)
Console.WriteLine("The padded string : " + objString.str.PadLeft(intStart,c));
else
Console.WriteLine("The padded string : " + objString.str.PadRight(intStart,c));
}
else
if ("Left"==strVal)
Console.WriteLine("The padded string : " + objString.str.PadLeft(intStart));
else
Console.WriteLine("The padded string : " + objString.str.PadRight(intStart));

}

private void mtdPadRight() {
mtdPad("Right");
}

private void mtdRemove() {
Console.WriteLine("String.Remove(int i,int j) - > removes a part of the string.'i' represents the start position and 'j' represents the length of string to be removed.");

Console.WriteLine("The original string : "+objString.str);
Console.Write("Enter the starting position : ");
int intStart=int.Parse(Console.ReadLine());
Console.Write("Enter the length of string to be removed :");
int intLength=int.Parse(Console.ReadLine());
Console.WriteLine("The string after removal :"+objString.str.Remove(intStart,intLength));
}

private void mtdReplace() {
Console.WriteLine("String.Replace() - > replaces a character with another character or a string with another string throughout the given string");

Console.WriteLine("1. String.Replace(char cOld,char cNew) -> replaces all occurances 'cOld' with 'cNew'");

Console.WriteLine("2. String.Replace(string sOld,strin sNew) -> replaces all occurances of 'sOld' with 'sNew'");

Console.Write("Enter your choice :");
int intChoice=int.Parse(Console.ReadLine());
Console.WriteLine("The original string is :"+objString.str);
if (1==intChoice) {
Console.Write("Enter the character to be replaced :");
char cold=(Console.ReadLine().ToCharArray())[0];
Console.Write("Enter the new character :");
char cnew=(Console.ReadLine().ToCharArray())[0];
Console.WriteLine("The string after replacing : "+objString.str.Replace(cold,cnew));
}
else {
Console.Write("Enter the string to be replaced :");
string sold=Console.ReadLine();
Console.Write("Enter the new string :");
string snew=Console.ReadLine();
Console.WriteLine("The string after replacing : "+objString.str.Replace(sold,snew));

}
}

private void mtdSplit() {
Console.WriteLine("This will be done later.");
}

private void mtdStartsWith() {
Console.WriteLine("String.StartsWith(string str) - > returns a boolean value indicating whether the string starts with 'str'");

Console.WriteLine("The original string : "+ objString.str);
Console.Write("Enter the string to search for :");
string strTmp=Console.ReadLine();
if (objString.str.StartsWith(strTmp))
Console.WriteLine("The string '"+objString.str+"' starts with '"+strTmp+"'.");
else
Console.WriteLine("The string '"+objString.str+"' does not starts with '"+strTmp+"'.");
}

private void mtdSubStr() {
Console.WriteLine("String.Substring() - > retrieves a part of the string from the original string");
Console.WriteLine("1. String.Substring(int i) -> retrieves the string starting from 'i'(zero based)");
Console.WriteLine("2. String.Substring(int i,int j) -> retrieves the string starting from 'i' and having a length 'j'.");

Console.Write("Enter your choice :");
int intChoice=int.Parse(Console.ReadLine());
int intStart,intLength;
Console.WriteLine("The original string :"+objString.str);
if (1==intChoice) {
Console.Write("Enter the position from where the substring should start :");
intStart=int.Parse(Console.ReadLine());
Console.WriteLine("The retrieved substring is :"+objString.str.Substring(intStart));
}
else {
Console.Write("Enter the position from where the substring should start :");
intStart=int.Parse(Console.ReadLine());
Console.Write("Enter the length of the substring:");
intLength=int.Parse(Console.ReadLine());
Console.WriteLine("The retrieved substring is :"+objString.str.Substring(intStart,intLength));
}
}

private void mtdLower() {
Console.WriteLine("String.ToLower() - > returns the string with all its characters in lower case");
Console.WriteLine("The original string : " + objString.str);
Console.WriteLine("The string in lower case : " +objString.str.ToLower());
}

private void mtdUpper() {
Console.WriteLine("String.ToUpper() - > returns the string with all its characters in upper case");
Console.WriteLine("The original string : " + objString.str);
Console.WriteLine("The string in upper case : " +objString.str.ToUpper());
}

private void mtdTrim() {
Console.WriteLine("String.Trim() - > removes white space characters from the begininning and end of the string and also specified characters.");

Console.WriteLine("1. String.Trim() -> removes white space characters from beginning and end of the string.");

Console.WriteLine("2. String.Trim(char[] c) -> removes all occurances of set of characters in the array from the beginning and end of string.");

Console.Write("Enter your choice :");
int intChoice=int.Parse(Console.ReadLine());
Console.WriteLine("The original string : " +objString.str);
if (1==intChoice) {
Console.WriteLine("The trimmed string is : "+objString.str.Trim());
}
else {
Console.Write("Enter the character array : ");
char[] c=Console.ReadLine().ToCharArray();
Console.WriteLine("The string after removing characters from the array : " + objString.str.Trim(c));

}
}

private void mtdTrimEnd() {
Console.WriteLine("String.TrimEnd(char[] c) - > removes all occurances of the set of characters in the array from the end of the string.");

Console.WriteLine("The original string is : " + objString.str);
Console.Write("Enter the character array : ");
char[] c=Console.ReadLine().ToCharArray();
Console.WriteLine("The modified string is : "+objString.str.TrimEnd(c));
}

private void mtdTrimStart() {
Console.WriteLine("String.TrimStart(char[] c) - > removes all occurances of the set of characters in the array from the start of the string.");

Console.WriteLine("The original string is : " + objString.str);
Console.Write("Enter the character array : ");
char[] c=Console.ReadLine().ToCharArray();
Console.WriteLine("The modified string is : "+objString.str.TrimStart(c));
}
} (转贴)