C#----String的常用成员函数

String str1 = "123114511";//比较Console.WriteLine (str1.CompareTo ("11344"));//1Console.WriteLine (String.Compare ("123", "345"));//-1Console.WriteLine (String.Equals ("2", "3"));//false               //索引Console.WriteLine (str1.Insert (2, "abc"));//12abc345Console.WriteLine (str1.IndexOf ("34"));//2，返回索引Console.WriteLine (str1.Trim ('1'));//删除前面的和后面的 1//C#中没有类似于C++中，string.at的函数,但是可以直接用索引Console.WriteLine (str1 [3]);//2Console.WriteLine (str1.StartsWith ("123"));//是不是以123开头的，true