CString a,b;
a = "123456789";
b = a.Left(4); //值为:1234
b = a.Mid(3); //值为:456789
b = a.Mid(2, 4); //值为:3456
b = a.Right(4); //值为:6789spa
a.Trim();//去掉俩侧空格im
a.TrimLeft(12);//去掉左边指定字符,值为:3456789co
a.TrimRight(89);//去掉右边 指定字符,值为:1234567字符
a.Replace(3,#);//替换,把3替换成#,值为12#456789background
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