Question

C#中怎样从一个文件读取内容然后写到另一个文件中去

下面是我的程序，我的文档其实都已经创立了，但是wsx.txt已经存在，就是内容为空。
private void open_Click(object sender, RoutedEventArgs e)
{

OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.FileName = "Members.txt";
openFileDialog.DefaultExt = "txt";
string fullPathName = openFileDialog.FileName;
//StreamWriter writer = new StreamWriter("wsx.txt");
//writer.WriteLine("wsxxxxx");
if (openFileDialog.ShowDialog().Value)
{
StreamWriter writer = new StreamWriter(@"C:\Users\wangshuxing\Documents\wsx.txt");
// writer.WriteLine("wsxxxxx");
string name = openFileDialog.FileName;//提供完整的文件路径
FileInfo file = new FileInfo(name);
// MessageBox.Show(file.Name,"代开的文件");//仅仅提供文件的名称。
TextReader reader = file.OpenText();
string line = reader.ReadLine();//为什么就是不能往里写数据呢？？？

while (line != null)
{
writer.WriteLine(line);
line = reader.ReadLine();
}
reader.Close();

}

Answer 1

// Try:
using System.IO; // 添加此引用

StreamWriter writer = new StreamWriter(@"C:\Users\wangshuxing\Documents\wsx.txt");
               // writer.WriteLine("wsxxxxx");
                string name = openFileDialog.FileName;//提供完整的文件路径
                FileInfo file = new FileInfo(name);
                // MessageBox.Show(file.Name,"代开的文件");//仅仅提供文件的名称。
                StreamReader reader = file.OpenText(此处写读取文件的路径);
                string line;
                
                while(null!=(line=reader.ReadLine())) writer.WriteLine(line);
                    
                
                reader.Close();

Answer 2

FileStream rfs =new FileStream("源文件路径"，FileMode.Open,FileAccess.Read);//打开源文件读

FileStream wfs =new FileStream("目标文件路径"，FileMode.Create,FileAccess.Write);//打开源文件读

for(int i=0;i<rfs.Lneght;i++) wfs.WriteByte(rfs.ReadByte()); //从一个文件写到另一个文件

rfs.dispose();
wfs.dispose(); //用完释放

Answer 3

在whlie循环后面加上writer.Flush();

Answer 4

用StreamReader，一般StreamWriter和 StreamReader是配套使用的