Splitting of string in c# language

// Method invoke Place 
String strInput= "Solve OP1 + OP2 and |*OP1 + OP2*| and find out answer of |*OP1 / OP2*| with correct logic.";
StringSplit(strInput);


private static void StringSplit(string strInput)
{
      List<string> lstOutput = new List<string>();
    
    string currentStr = string.Empty;
    currentStr  = strInput;
   string splitStart = "|*";
   string splitEnd = "*|";

   while (currentStr != string.Empty)
  {
           if(currentStr.Substring(0,2) != splitStart)
           {
                   string strnew ="";
                  if(currentStr.IndexOf(splitStart)>0)
                 {
                              strnew = currentStr.Substring(0, currentStr.IndexOf(splitStart));
                              currentStr =  currentStr.Substring( currentStr.IndexOf(splitStart),  currentStr.Length -  currentStr.IndexOf(splitStart)); 
                 } 
                 else
                {
                             strnew = currentStr;
                             currentStr ="";
                }
               lstOutput.Add(strnew);
           }
           else if (currentStr.Substring(0,2) == splitStart)
           { 
                  string strnew= currentStr.Substring(0, currentStr.IndexOf(splitEnd)+2);
                 lstOutput.Add(strnew);
                currentStr =currentStr.Substring(currentStr .IndexOf(splitEnd)+2, currentStr.Length - currentStr.IndexOf(splitEnd)-2);
           }
  } //end of while


//binding Output
foreach( string s in lstOutput)
{
   Console.WriteLine(s); 
}

}

public string[] GetArray(string strdata)
    {
        //      Solve OP1 +OP2 and
        //      | *OP1 + OP2 *|
        //      and find out answer of
        //      | *OP1 / OP2 *|
        //      with correct logic.


        strdata = "Solve OP1 + OP2 and |*OP1 + OP2*| and find out answer of |*OP1 / OP2*| with correct logic.";
        
 
        int iCounter = 0;
        int firstIndex = strdata.IndexOf("|*");
        int secondIndex = (strdata.IndexOf("*|") - firstIndex) + 2;


        string part1 = strdata.Substring(0, firstIndex);
        string part2 = strdata.Substring(firstIndex, secondIndex);
        string part3 = strdata.Substring((secondIndex + firstIndex), firstIndex + 3);
        iCounter = part1.Length + part2.Length + part3.Length;
        string part4 = strdata.Substring(iCounter, secondIndex + 1);
        iCounter += part4.Length;
        string part5 = strdata.Substring(iCounter, strdata.Length - iCounter);
        string separator = "::";

        string finalData = string.Format("{0}" + separator + "{1}" + separator + "{2}" + separator + "{3}" + separator + "{4}", part1, part2, part3, part4, part5);

        return finalData.Split(separator);

    }