C#入门篇6-2：字符串操作 string常用的函数

//String 字符串的常见操作
public static void Fun1()
{
string MyStr = " Hello World! ";

//length长度属性
Console.WriteLine(MyStr.Length);

//Substring()截取
Console.WriteLine(MyStr.Substring(0, 5));

//ToCharArray()转换为字符数组
char[] charr = MyStr.ToCharArray();

//ToUpper()转换大写
string UpperStr = MyStr.ToUpper();
Console.WriteLine("转换为大写：" + UpperStr + "\n");

//ToLower()转换小写
Console.WriteLine("转换为小写：" + MyStr.ToLower());

//TrimStart() and TrimEnd() 去掉字符左右边的空格 TrimStart--去掉左边
string LefStr = MyStr.TrimStart();
string RigStr = MyStr.TrimEnd();

Console.WriteLine("左边 " + LefStr + "\n" + "右边 " + RigStr + "\n");

//Replace()替换字符
string ReplaceStr = MyStr.Replace('W', 'M');
Console.WriteLine("替换字符 " + ReplaceStr + "\n");

//Concat()连接字符
string concatStr = string.Concat(MyStr, "asas", "asasa");
Console.WriteLine("连接字符 " + concatStr + "\n");

//IsNullOrEmpty()判断空值
bool NullorEmpty = string.IsNullOrEmpty(MyStr);
Console.WriteLine("判断空值 " + NullorEmpty.ToString() + "\n");

//StartsWith()开头
Console.WriteLine(MyStr.StartsWith(" ") == true);

//EndsWith()结尾
bool endwith = MyStr.EndsWith(" ");
Console.WriteLine("结尾 " + endwith.ToString() + "\n");

//IndexOf() and LastIndexOf()字符串的位置
string strLocation = "123abc4c56efd";
Console.WriteLine("IndexOf:" + strLocation.IndexOf('1') + "\n");
Console.WriteLine("LastIndexOf:" + strLocation.LastIndexOf('c') + "\n");

//插入字符
Console.WriteLine(MyStr.Insert(2, "W"));

//MyStr.PadLeft();MyStr.PadRight()

//Remove()移除
Console.WriteLine("Remove:" + strLocation.Remove(0, 1) + "\n");

//Format()格式化
string str = string.Format("{0:X4}", 3);
Console.WriteLine(str);

//Compare()和CompareTo() 比较方法
string strA = "File.exe";
string strB = "0";

int numA = string.Compare(strA, strB);
Console.WriteLine("Compare: " + numA.ToString() + "\n");

int numB = strA.CompareTo(strB);
Console.WriteLine("CompareTo: " + numB.ToString());

//比较两个指定的 System.String 对象。
// 返回结果:
// 一个 32 位有符号整数，指示两个比较数之间的词法关系。
//值条件小于零 strA 小于 strB。 零strA 等于 strB。 大于零 strA大于 strB。

}