C# file操作

file操作

file类

using System;
using System.IO;

namespace _31_file类
{
    class Program
    {
        static void Main(string[] args)
        {
            File.Create(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级2--面向对象继承2video
ew.txt");
            Console.WriteLine("创建成功");
        }
    }
}

创建一个文件 File.Create()

File.Create(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级2--面向对象继承2video
ew.txt");

删除一个文件File. Delete()

File.Delete(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级2--面向对象继承2video
ew.txt");

复制一个文件 File.Copy(file,new_file)

File.Copy(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级2--面向对象继承1资料.rar", @"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级2--面向对象继承2video资料.rar");

Bytes 字节

读数据 File.ReadAllBytes()

byte[] buffer = File.ReadAllBytes(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt");
string s = Encoding.GetEncoding("UTF-8").GetString(buffer);
Console.WriteLine(s);

写入数据 File.WriteAllBytes(file,data)

string s = "hello Irving";

byte[] buffer = Encoding.Default.GetBytes(s);
File.WriteAllBytes(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", buffer );

string[] 数组

读取文件为数组 File.ReadAllLines(file, Encoding)

string[] s = File.ReadAllLines(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", Encoding.Default);
Console.WriteLine(s);
foreach (var item in s)
{
    Console.WriteLine(item);
}

数组格式的数据保存文件 File.WriteAllLines(file, new string[]{})

File.WriteAllLines(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", new string[] { "dsfsdf", "hello" });

text 文本

读取文件为文本 File.ReadAllText(file, Encoding)

string s = File.ReadAllText(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", Encoding.Default);
Console.WriteLine(s);

文本格式的数据保存文件 File.WriteAllText(file, text)

File.WriteAllText(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", "fhgkfdshgk");

追加文本格式数据

File.AppendAllText(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", "
hello");

FileStream 类

fileStream 读取文件

using System;
using System.IO;
using System.Text;

namespace _32_FileStream
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
            // FileStream 操作字节的
            // StreamReader和StreamWriter 是操作字符的
            FileStream fsRead = new FileStream(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", FileMode.OpenOrCreate, FileAccess.Read);
            byte[] buffer = new byte[1024*1024*5];  // 用于存放字节数据
            int r = fsRead.Read(buffer,0,buffer.Length);    // 返回实际读取的有效字节数
            string s = Encoding.Default.GetString(buffer, 0, r);  // 字节转字符串
            Console.WriteLine(s);

            // 释放所有占用资源
            fsRead.Close();
            fsRead.Dispose();

        }
    }
}

 fileStream 写入文件 

fs.SetLength(0); 清空

using (FileStream fs = new FileStream(@"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt", FileMode.OpenOrCreate, FileAccess.Write))
{
    string s = "我来覆盖你";
    byte[] buffer = Encoding.Default.GetBytes(s);
    fs.SetLength(0); //清空
    fs.Write(buffer, 0, buffer.Length);
}

文件复制

using System;
using System.IO;
using System.Text;

namespace _32_FileStream
{
    class Program
    {
        static void Main(string[] args)
        {
            string source = @"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.txt";
            string target = @"F:BaiduNetdiskDownload1.Net基础教程1.Net基础3-c#高级3--面向对象多态1video
ew.bak.txt";

            CopyFile(source, target);
        }

        public static void CopyFile(string source, string target)
        {
            // 创建一个负责读取的流
            
            using (FileStream fs = new FileStream(source, FileMode.Open, FileAccess.Read))
            {
                using (FileStream fs_write = new FileStream(target, FileMode.OpenOrCreate, FileAccess.Write))
                {
                    int size = 0;
                    while (true)
                    {
                        byte[] buffer = new byte[1024 * 1024 * 5];
                        int r = fs.Read(buffer, 0, buffer.Length);
                        if (r==0) return;
                        
                        fs_write.Write(buffer, 0, r);
                        size += r;
                    }

                }
            }
            
        }
    }
}

 StreamReader

StreamReader 读取字符

//StreamReader
using (StreamReader sr = new StreamReader(source, Encoding.Default))
{
    while (!sr.EndOfStream)
    {
        Console.WriteLine(sr.ReadLine());
        Console.WriteLine(sr.Read());
    }
}

StreamWriter

StreamWriter 写入字符

using (StreamWriter sw = new StreamWriter(source, true))
{

    sw.Write("山东i过后四大公害世噶啥的回
复收到回复
");
    //sw.WriteL("山东i过后四大公害世噶啥的回复收到回复");
    sw.WriteLine("山东i过后四大公害世噶啥的回复收到回复");
}