C#（三十九）之关于string的一些函数

// startswith  字符串以。。。开头
            string[] strArr = { "asd","azx","qwe","aser","asdfgh"};
            for (int i = 0; i < strArr.Length; i++)
            {
                if(strArr[i].StartsWith("as"))
                {
                    Console.WriteLine(strArr[i]);
                }
            }

// endswith  字符串以。。。结尾
            for (int i = 0; i < strArr.Length; i++)
            {
                if(strArr[i].EndsWith("d"))
                {
                    Console.WriteLine(strArr[i]);
                }
            }

// IndexOf  查找第一次在字符串中出现的位置（字符串，从哪里开始找）
            string str = "hello world";
            int index = str.IndexOf("ll",0);
            Console.WriteLine(index);

char[] rest = { 'o', 'l' };
            int xx = str.IndexOfAny(rest);
            Console.WriteLine(xx);

string a = str.Substring(4);
            string b = str.Substring(4,6);
            Console.WriteLine(a);
            Console.WriteLine(b);

string[] sd = str.Split(' ');
            for (int i = 0; i < sd.Length; i++)
            {
                Console.WriteLine(sd[i]);
            }

// 字符串转大小写
            string az = "ASDasdfg";
            string q = az.ToUpper();
            Console.WriteLine(q);
            string w = az.ToLower();
            Console.WriteLine(w);

string kk = "I Love You";
            string sx = kk.Insert(3,"s");
            Console.WriteLine(sx);
            string sc = kk.Replace("s"," ");
            Console.WriteLine(sc);
            string sv = kk.Remove(2,4);
            Console.WriteLine(sv);

string asd = "  qwe  ";
            string asa = asd.Trim();
            Console.WriteLine(asa);

string str1 = "123";
            string str2 = "234";
            if (str1 == str2)
            {
                Console.WriteLine("true");
            }
            else
            {
                Console.WriteLine("false");
            }

// Equals
            if (str1.Equals(str2))
            {
                Console.WriteLine(true);
            }
            else
            {
                Console.WriteLine(false);
            }

if (Equals(str1, str2))
            {
                Console.WriteLine(true);
            }
            else
            {
                Console.WriteLine(false);
            }

string str3 = "中偶人";
string str4 = str3.PadRight(10,'2');
Console.WriteLine(str4);