How to update a record of a txt file in C# ?

Question

Hi,

Is it possible to update a record of a txt file in C#? In VB, we can do:

Open inFile For Random As #1 Len = 1156
Put #1 , recNum, outLine
Close #1

Here recNum is the specific record number which we want to update, outLine is the new record.

My question is that in C# do we have any way to do it or not? Or C# have any other way to update a record just like update in DB file.

So far, I can figure out a way is to write all the records from beginning to recNum -1, then write record recNum and then write the balance. finianlly delete the old file and rename the new file. This is very dummy way. I hope somebody can give me a better ideal.

Thanks you very much.

will he · Answer

I found the answer by myself. Below is the code: /// ///here, the data structure is fixlength and end by Crlf char("
"). /// public void updatedIt(string inFile, int recLen, int recNum) { // int byteLen, byteStartNum; FileStream fileInput = new FileStream(inFile, FileMode.Open, FileAccess.ReadWrite); BinaryWriter wr = new BinaryWriter(fileInput); try { fileInput.Seek((recNum-1)*(recLen), SeekOrigin.Begin); byte[] b = new byte[recLen-2]; ASCIIEncoding temp = new ASCIIEncoding(); b = temp.GetBytes(recStr); fileInput.Write(b, 0, recLen-2); } catch(IOException) { //close stream if no records in file MessageBox.Show("records number out of range","",MessageBoxButtons.OK, MessageBoxIcon.Information); fileInput.Close(); } fileInput.Close(); } Any questions, email to me: hezhqing@gmail.com

How to update a record of a txt file in C# ?

Answers (1)