get a line after a specific word from text file

Question

Hi All In my text file I have data like this: [data] 123.txt blabla [Mobile] 345.txt 456.txt [calls] vsjs.txt dsfs.txt I would like to get these data (345.txt 456.txt) and and the keyword to get is [Mobile]. I want to show 345.txt 456.txt in rich textbox. If user makes any changes than I want to save it back. It means If user writes 345test.txt then the text file should be like this: [data] 123.txt blabla [Mobile] 345test.txt 456.txt [calls] vsjs.txt dsfs.txt Advance thanks Darma

Vulpes · Answer

The following code assumes that there is only one [Mobile] section in the file and that the relevant lines will be loaded to the RTB when button1 is pressed and any changes saved when button2 is pressed: using System.IO; // .... private string filePath = @c:\myfiles\somefile.txt; // or whatever it is private string[] lines; private int startIndex; private string originalText = ; private int originalCount; private void button1_Click(object sender EventArgs e) { lines = File.ReadAllLines(filePath); var mobileLines = new List (); startIndex = -1; for(int i = 0; i { if (lines[i].StartsWith([Mobile])) { startIndex = i + 1; } else if(lines[i].StartsWith([) && startIndex > -1) { break; } else if(startIndex > -1) { mobileLines.Add(lines[i]); } } if(mobileLines.Count > 0) { richTextBox1.Lines = mobileLines.ToArray(); originalText = richTextBox1.Text; originalCount = mobileLines.Count; } } private void button2_Click(object sender EventArgs e) { if (richTextBox1.Text != originalText) { var allLines = lines.ToList(); allLines.RemoveRange(startIndex originalCount); allLines.InsertRange(startIndex richTextBox1.Lines); File.WriteAllLines(filePath allLines); } }

darma teja · Answer

Thanks allot Vulpes!

Vulpes · Answer

Just in case the user decides to make some changes and press button2 then make some more changes and press button2 again I'd add some lines to the button2_Click handler: private void button2_Click(object sender EventArgs e) { if (richTextBox1.Text != originalText) { var allLines = lines.ToList(); allLines.RemoveRange(startIndex originalCount); allLines.InsertRange(startIndex richTextBox1.Lines); File.WriteAllLines(filePath allLines); lines = allLines.ToArray(); originalText = richTextBox1.Text; originalCount = richTextBox1.Lines.Length; } } I'd also disable button2 until button1 has been pressed.