字符串截取

SubString OR Remove

1 1  string str3 = "123abc456";
2 2 
3 3  //str3 = str3.Substring(0, i);  //从左边开始取字符串的前i个字符(str3 = str3.Remove(i, str3.Length - i);)
4 4  str3 = str3.Substring(0, 3);
5 5  str3 = str3.Remove(3, str3.Length - 3);
6 6  //输出："123"
7 7 
8 8  //str3 = str3.Substring(i);     //从左边开始去掉字符串的前i个字符(str3=str3.Remove(0,i);)
9 9  str3 = str3.Substring(3);
1010  //输出："abc456"11 
1112  //str3 = str3.Substring(str3.Length - i);  //从右边开始取i个字符(str3=str3.Remove(0,str3.Length-i))
1213  str3 = str3.Substring(str3.Length - 3);
1314  //输出："456"
1415 
1516  //str3 = str3.Substring(0, str3.Length - i); //从右边开始去掉i个字符(str3=str3.Remove(str3.Length-i,i))
1617  str3 = str3.Substring(0, str3.Length - 3);
1718  //输出："123abc"

Trim

1 1   string str = " I Believe You Very Much! ";
2 2   str = str.TrimStart();                                  //截取掉字符串首部的空格
3 3   //输出："I Believe You Very Much! "
4 4 
5 5   str = str.TrimStart('I');                               //截取掉字符串第一个字符
6 6   //输出："Believe You Very Much! "
7 7 
8 8   str = str.TrimStart().TrimStart("Beli".ToCharArray());  //截取掉字符串首部及尾部出现的B或e或l或i字符,删除的过程直到碰到一个既不是B也不是e也不是l也不是i的字符才结束。
9 9   //输出："ve You Very Much! "
1010             
1111   string str1 = " I Believe You Very Much! ";
1212   str = str1.Trim();                                      //截取掉字符串首部和尾部的空格
1313   //输出："I Believe You Very Much!"
1414             
1515   //TrimEnd的方法和TrimStart原理一样不多赘述
1616   string str2 = " I Believe You Very Much! ";
1717   str = str2.TrimEnd();                                   //截取掉字符串首部和尾部的空格
1818   //输出：" I Believe You Very Much!"

字符串替换

Replace

11   string str5 = "123abc456efg";
22   str5 = str5.Replace("efg", "EFG");
33   //输出："123abc456EFG"

字符串分割

Split

11    string str6 = "123,abc,456,efg";
22    string[] str6s = str6.Split(',');
33    foreach (var item in str6s)
44    {
55          ConsoleStr(item);
66    }
77    //输出："123 abc 789 efg"

字符串连接

Join

11 //结合split里面的字符串数组str6s
22 string str7 = string.Join("-", str6s);
33 //输出："123-abc-456-efg"

字符串转换大小写

11  string str8 = "abcdefgHIJK";
22  str8 = str8.ToUpper();
33  //输出："ABCDEFGHIJK"
44 
55  str8 = str8.ToLower();
66  //输出："abcdefghijk"
77 
88  bool isUpper = char.IsUpper(str8, 8);
99  //输出："True"

字符串比较

1 1   string str10 = "abackhdk";
2 2 
3 3   string str9 = "abac";
4 4   int aa = str9.CompareTo(str10);
5 5    //输出："-1"
6 6 
7 7   string str11 = "b";
8 8   int bb = str11.CompareTo(str10);
9 9   //输出："1"
1010 
1111   string str12 = "abackhdk";
1212   int cc = str12.CompareTo(str10);
1313   //输出："0"

查找子串

11 str.IndexOf(子串，查找其实位置) ;
22 str.LastIndexOf(子串) ;最后一次出现的位置
33 str.IndexOf("ab",0);

插入子串

11 str.Insert(插入位置，插入子串) ;
22 s.Insert(2,"ab");

移出子串

这里Remove我已经和Substring一起说了。就不细说了

11 str.Remove（其实位置，移出数）;
22 s.Remove(3,2);