[C++] 常用工具类

a.EndsWith(x)  是否以x结尾
a.Equals(b)  判断a,b是否相同
a = String.Format(fmt, args)  格式化
index = a.IndexOf(sub)  判断子串是否存在
a.Insert(index , sub)  插入一个子串
String.IsNullOrEmpty(a)  判断是否null或为空串
index = a.LastIndexOf(sub)  从后面查找一个子串
a.Remove(index, count)  删除一部分子串
a.Replace(oldstr, newstr)  查找并替换子串
a.Split( ccc )  分割
a.StartsWith(x )  判断是否以x开头
a.Substring(start, length)  获取子串
a.ToLower() / a.ToUpper()  转成小写/大写a.Trim()去除空白

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Major;
namespace CSharp基础语法
{

  class Program
  {
    static void Main(string[] args)
    {
      string str = "id,name,age,sex,phone,addree";
      string[] s = str.Split(',');
      foreach(string item in s)
      {
        Console.WriteLine(item);
      }
      
    }
  }
}

DateTime dt1 =new DateTime(2020,1,29);

DateTime dt2 = DateTime.Now;
int year = dt2.Year;
int hour = dt2.Hour;

String str = dt2.ToString("yyyy-MM-dd HH:mm:ss");

DateTime dt3= DateTime.ParseExact("2020/1/29",
"yyyy/M/d",
CultureInfo.InvariantCulture);

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Major;
namespace CSharp基础语法
{

  class Program
  {
    static void Main(string[] args)
    {
      // 创建一个DateTime对象
      DateTime dt1 = new DateTime(2020, 1, 29);
      // 当前时间
      DateTime dt2 = DateTime.Now;
      int year = dt2.Year;
      int hour = dt2.Hour;
      // DateTime -> String 
      String str = dt2.ToString("yyyy-MM-dd HH:mm:ss");
      // String -> DateTime
      DateTime dt3 = DateTime.ParseExact("2020/1/19", "yyyy/M/d", CultureInfo.InvariantCulture);
      // 历法计算
      DateTime dt4 = dt3.AddDays(-10);
      Console.WriteLine("10天前：" + dt4.ToString("yyyy-MM-dd"));
      // 时间差 interval  = t1.Subtract(t2)
      TimeSpan interval = DateTime.Now.Subtract(new DateTime(1990,1,1));
      double milli = interval.TotalMilliseconds;
      Console.WriteLine(milli);

    }
  }
}

File , FileInfo ：文件的创建、复制、删除、移动
Directory, DirectoryInfo：目录的创建、删除、移动和枚举
Path：文件目录的路径处理

Directory.CreateDirectory("c: \ \ test \ lxl lyl\z");

string dirPath = "c: \ \ test \ x \ly\\z";
DirectoryInfo dir = new DirectoryInfo(dirPath);
dir.Create();

File.Move( path1,path2);

FileInfo info =new FileInfo(filePath);
long size = info.Length;
DateTime time = info.LastWriteTime;

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Basic1503
{
  class Program
  {
    public static void TestDirectory()
    {
      // 文件操作
      Directory.CreateDirectory("c:\\test\\x\\y\\z");
      Directory.CreateDirectory(@"c:\test\haha");
      string dirPath = "c:\\test\\x\\y\\z";
      DirectoryInfo dir = new DirectoryInfo(dirPath);
      dir.Create();
    }
    public static void TestFile()
    {
      string filePath = "c:\\test\\abc.txt";
      FileInfo info = new FileInfo(filePath);
      long size = info.Length;
      DateTime time = info.LastWriteTime;
      // 注意：win10下不能在根目录下创建文件，必须先建立一个子目录
      File.Move(filePath, "c:\\test\\123.txt");
    }
    static void Main(string[] args)
    {
      TestDirectory();
      //TestFile();

      Console.WriteLine("Exit");
    }
  }
}