using System;
using System.Text;

namespace 字符串方法
{
class Program
{
static void Main(string[] args)
{
//1.
string s = " wei715547";
int res = s.CompareTo("wei715547");//元素相等时,返回值为0,
//调用者字母排序靠后时返回值为1,靠前是返回值为-1
Console.WriteLine(res);

        //2
        string newstring = s.Replace('w', 'z');//替换字符
        Console.WriteLine(newstring );
        //string newstring2 = s.Replace('1', '2');

        //3.字符串从指定字符位置拆分为数组
        string[] stringArray = s.Split('1');
        foreach (var item in stringArray )
        {
            Console.WriteLine(item );
        }
        string s = "abc-----[[[[####wei"
        string sArray = str.Split(new char[]{'-','[','#'},StringSplitOption.RemoveEmptyEntries)//将字符数组中的元素置换为空,字符截取选项移除空项-返回字符串数组

        //4.Substring.截取字符串
        string newcut = s.Substring(2,5);
        Console.WriteLine(newcut);

        //5.清除字符串首尾空白
        string clearspace = s.Trim();
        Console.WriteLine(clearspace );

        //6.返回指定字符的索引
        int newindex = s.IndexOf('1');
        Console.WriteLine(newindex );

        //7.

        //-------------------------------------------------------------
        //可变字符串StringBuilder 
        //create1.通过构造函数进行构建
        StringBuilder sb = new StringBuilder("www.wei7157.github.co");
        Console.WriteLine(sb);
        //create2.声明空间大小
        StringBuilder sb2 = new StringBuilder(20);
        sb2.Append("www.wei7157.github.co");
        Console.WriteLine(sb2);
        //creat3.赋值同时声明空间大小
        StringBuilder sb3 = new StringBuilder("www.wei7157.github.co", 100);
        Console.WriteLine(sb3);


        //字符串修改与标准字符串对比
        sb.Append("000000");//在空余空间链接字符
        Console.WriteLine(sb);
        (可用于追加Html代码实现网页内容)

        //对比常规字符串操作,运行效率更高
        string str = "www.wei7157.github.co";
        str += "000000";//在堆中创建新的字符,str索引指向新的字符,原来的字符被CLR回收(效率低)
        Console.WriteLine(str);

        //可变字符串Insert()方法
        sb.Insert(0, "http//");
        Console.WriteLine(sb);
        sb.Remove(0, 6);//根据索引范围移除字符
        Console.WriteLine(sb);
        sb.Replace('w', 'z');//字符替换
        Console.WriteLine(sb);
        Console.WriteLine(sb.ToString());//ToString()转变为不可变字符

    }
}

}