Delete Lines from multiline textbox if it's contain certain string - C#

Question

Hello!

I have a multiline texbox, and would like delete lines if it's contain some string.

Example

Line 1 abababalanlndw

Line 2 aaaaakkk knlnflef baby efqwf

Line 3 fwelfnwaofna

If one of the lines contain the "baby" string, i have to delete this line!

Can you help me?

Answer 1

You can do it in a very elegant way using LINQ:

textBox1.Lines = textBox1.Lines.Where(line => !line.Contains("baby")).ToArray();

With this instruction, we keep only the lines that don't contain the word "baby".

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Marco Minerva [MCPD]
Blog: http://blogs.ugidotnet.org/marcom
Twitter: @marcominerva

Answer 2

Try the below function. Just pass the TextBox object and String to find.

private void RemoveLinesContainingToken(TextBox tb, String Token)
{
    String newText = String.Empty;
    List<String> lines = tb.Text.Split(new String[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries).ToList();
    lines.RemoveAll(str => str.Contains("baby"));
    lines.ForEach(str => newText += str + Environment.NewLine);
    textBox1.Text = newText;
}

Now, suppose you want to delete all lines containing "baby" from a TextBox called textBox1, you can call above method as,

RemoveLinesContainingToken(textBox1, "baby");

I hope this helps.

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Please mark this post as answer if it solved your problem. Happy Programming!

Answer 3

Hi poli12,

Besides, you may use Regular expressions, or using the code as in this thread: remove textbox lines that contain certain string.

Sincerely,

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Helen Zhou [MSFT]
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