How can search back slash character in string?

/// <summary>
       /// This method returns count of specified character in a string.
       /// </summary>
       /// <param name="stringForProcessing">Determines instance of string class that contains specifiedCharacter</param>
       /// <param name="specifiedCharacter">Determines specified character for searching. </param>
       /// <returns></returns>
       private int GetCountOfOccurance(string stringForProcessing, char specifiedCharacter)
       {
           int result = 0;
           foreach (char letter in stringForProcessing)
           {
               if (letter.Equals(specifiedCharacter))
               {
                   result++;
               }
           }
           return result;
       }