1 private void Replace(string oldStr, string newStr, string file)
2 {
3 FileStream fs = File.OpenRead(file);
4 //to know if this file is text file or binary file
5 byte b;
6 for (long i = 0; i < fs.Length; i++)
7 {
8 b = (byte)fs.ReadByte();
9 if (b == 0)
10 {
11 MessageBox.Show("Not Text File");
12 return;//if there is this byte then this is not text file。
13 }
14 }
15 //Judge the type of encoding。
16 byte[] bytes = new byte[2];
17 Encoding coding = Encoding.Default;
18 if (fs.Read(bytes, 0, 2) > 2)
19 {
20 if (bytes == new byte[2] { 0xFF, 0xFE }) coding = Encoding.Unicode;
21 if (bytes == new byte[2] { 0xFE, 0xFF }) coding = Encoding.BigEndianUnicode;
22 if (bytes == new byte[2] { 0xEF, 0xBB }) coding = Encoding.UTF8;
23 }
24 fs.Close();
25
26 string text = File.ReadAllText(file,coding);
27 File.WriteAllText(file, text.Replace(oldStr, newStr), coding);
28 }
