c# - 使用StreamReader复制图像时损坏

Question

是代码中的问题。
我正在尝试读取.gif文件并写入另一个.gif文件，如果我这样做...新创建的.gif文件将不会显示正确的图像，插入的垃圾图像是代码错误。

 private void ReadFile()
    {
        StreamReader MyReader = new StreamReader(@"C:\\Users\\admin\\Desktop\\apache_pb22_ani.gif");
        string ReadFile= MyReader.ReadToEnd();
        MyReader .Close ();

        StreamWriter MYWriter = new StreamWriter(@"C:\\Hi.gif");
        MYWriter.Write(ReadFile);
        MYWriter.Close();

        //throw new NotImplementedException();
    }

如果我从服务器读取图像并且如果我写入图像文件，也会出现相同的问题，那是什么问题...
从服务器读取图像并写入的代码在这里

StringBuilder sb = new StringBuilder();
        // used on each read operation
        byte[] buf = new byte[8192];
        // prepare the web page we will be asking for
        HttpWebRequest request = (HttpWebRequest)
                WebRequest.Create("http://10.10.21.178/Untitled.jpg");
        // execute the request
        HttpWebResponse response = (HttpWebResponse)
                request.GetResponse();
        // we will read data via the response stream
        Stream resStream = response.GetResponseStream();

        string tempString = null;
        int count = 0;

        StreamWriter FileWriter = new StreamWriter("C:\\Testing.jpg");


        do
        {
            // fill the buffer with data
            count = resStream.Read(buf, 0, buf.Length);
            // make sure we read some data
            if (count != 0)
            {
                // translate from bytes to ASCII text. 
                // Not needed if you'll get binary content.

                tempString = Encoding.ASCII.GetString(buf, 0, count);
                FileWriter.Write(tempString);
                // continue building the string
                sb.Append(tempString);
            }
        }
        while (count > 0); // any more data to read?

        FileWriter.Close();

        // print out page source
       // Console.WriteLine(sb.ToString());
        //throw new NotImplementedException();
    }

Answer 1

二进制数据（例如图像）在.NET字符串中不起作用；您想要类似的东西（假设没有File.Copy选项）：

using(Stream source = File.OpenRead(fromPath))
using(Stream dest = File.Create(toPath)) {
    byte[] buffer = new byte[1024];
    int bytes;
    while((bytes = source.Read(buffer, 0, buffer.Length)) > 0) {
        dest.Write(buffer, 0, bytes);
    }
}

这会将图像视为二进制（ byte[]），并使用缓冲区/循环来避免在图像较大时爆炸（当 File.ReadAllBytes可能很昂贵时）。