Question

C#如何将一段文本写入到一个文本文件中?

文件名为a.txt，文本内容为abcdefg，文件a.txt需要保存到的路径为D:\folder\

如果a.txt存在，在其已有的内容后面写入abcdefg，如果a.txt不存在，新建a.txt文件，然后写入abcdefg

Answer 1

楼主好懒，MSDN里面搜System.IO里面就有了

class Test
{

public static void Main()
{
string path = @"c:\temp\MyTest.txt";

// Delete the file if it exists.
if (File.Exists(path))
{
File.Delete(path);
}

//Create the file.
using (FileStream fs = File.Create(path))
{
AddText(fs, "This is some text");
AddText(fs, "This is some more text,");
AddText(fs, "\r\nand this is on a new line");
AddText(fs, "\r\n\r\nThe following is a subset of characters:\r\n");

for (int i=1;i < 120;i++)
{
AddText(fs, Convert.ToChar(i).ToString());

}
}

//Open the stream and read it back.
using (FileStream fs = File.OpenRead(path))
{
byte[] b = new byte[1024];
UTF8Encoding temp = new UTF8Encoding(true);
while (fs.Read(b,0,b.Length) > 0)
{
Console.WriteLine(temp.GetString(b));
}
}
}

private static void AddText(FileStream fs, string value)
{
byte[] info = new UTF8Encoding(true).GetBytes(value);
fs.Write(info, 0, info.Length);
}
}