string s = "1.53sG1";
string sh=s.Substring(s.Length - 1);
bool isShuZi=Regex.IsMatch(sh,@"^\d+$");

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C# code


string s = "1.53sG1";
string sh=s.Substring(s.Length - 1);
bool isShuZi=Regex.IsMatch(sh,@"^\d+$");