help with stream builder

Question

I have a form with three textboxes and a button. The user enters data into the said textboxes and pushes a button. Upon clicking streamreader queries a txt file for specific lines. I'm trying to overwrite these three lines with the data from my textboxes. However instead of overrating these lines it just places new lines below the original lines. So I end up with six lines instead of (three with the original data and three with data from texboxes 1 - 3). How can I get this to overwrite the orginal three lines with the new data? private void button23_Click(object sender EventArgs e) { StringBuilder sb = new StringBuilder(); string line = string.Empty; // path of the file using (StreamReader fs = new StreamReader(@c:	est.txt true)) { //checks until end of file while ((line = fs.ReadLine()) != null) { // This will serch a txt file for the word payload if (line.ToLower().StartsWith(center)) //This will override the sentence.... sb.AppendLine(Center1 = This is a test + textbox1 + end of test); if (line.ToLower().StartsWith(left)) //This will override the sentence.... sb.AppendLine(Left = This is a test + textbox2 + end of test); if (line.ToLower().StartsWith(right)) //This will override the sentence.... sb.AppendLine(Right = This is a test + textbox3 + end of test); sb.AppendLine(line); } } // path to my file // don't forget to close streamwriter // This should overwrite the lines. using (StreamWriter sw = new StreamWriter(@c:	est false)) { sw.Write(sb.ToString()); sw.Close(); } }

matthew king · Answer

No Worries Mr. Bar...mixing up the code is the story of my life...hence all the questions. I tried the new code...this time it excuted but left me with a blank text.txt. I have three books in front of me and I'm going to figure this out. Thanks for your help!!!!

Roei Bar · Answer

hey there matthew i got mixed up in code : List textList = new List (); List newTextList = new List (); //set filepath as the path to your test file the entire path //like @C:\test.txt //It will read all lines and then run on the list //Performing the logic you specified for lines that are from the type //you looked for insert the rows in the same order to a new List //and the //File.WriteAllLines(filepath newTextList .ToArray()); //will overwrite the file with the new lines textList.AddRange(File.ReadAllLines(filepath); foreach (string line in textList) { string newLine = string.Empty; if (line.ToLower().StartsWith(center)) { newLine = Cneter = This is a test + textbox2 + end of test; } if (line.ToLower().StartsWith(left)) { newLine = Left = This is a test + textbox2 + end of test; } if (line.ToLower().StartsWith(right)) { newLine = Right = This is a test + textbox2 + end of test; } if(newLine != line) newTextList.Add(newline); else newTextList.Add(line); } // Write to file File.WriteAllLines(filepath newTextList .ToArray());

matthew king · Answer

Mr. Bar...Good morning sir I tried the code but it appears to just keep looping. I put a breakpoint on the button23_Click event and then debugged...it just kept reading each line over and over but never updated the test.txt.

Roei Bar · Answer

here is the fixed code List textList = new List (); List newTextList = new List (); textList.AddRange(File.ReadAllLines(filepath); foreach (string line in textList) { string newLine = string.Empty; if (line.ToLower().StartsWith(center)) { newLine = Cneter = This is a test + textbox2 + end of test; } if (line.ToLower().StartsWith(left)) { newLine = Left = This is a test + textbox2 + end of test; } if (line.ToLower().StartsWith(right)) { newLine = Right = This is a test + textbox2 + end of test; } if(newLine != line) newTextList.Add(newline); else newTextList.Add(line); } // Write to file File.WriteAllLines(filepath textList.ToArray());