Get the part of a string before new line symbol

Question

I do want to get all the text before the first \r\n\ symbol. For example,

lalal lalal laldlasdaa daslda\r\n\Prefersaasda reanreainrea

I would need: lalal lalal laldlasdaa daslda. The above string can be empty, but it also may not contain any '\r\n\' symbol." How can I achieve this?

Possible duplicate of [Easiest way to split a string on newlines in .NET?](http://stackoverflow.com/questions/1547476/easiest-way-to-split-a-string-on-newlines-in-net) — VinKel, Jan 09 '17 at 08:17
Please note your input is not a valid string, their is an additional `\` after `\r\n` that make this input invalid — sujith karivelil, Jan 09 '17 at 08:23
That is not a good duplicate since it has too much overhead compared to the answers given @VinKel — Patrick Hofman, Jan 09 '17 at 08:33

score 7 · Accepted Answer · edited May 23 '22 at 23:19

7

You can use IndexOf to get the position, then use Substring to get the first part:

string s = "lalal lalal laldlasdaa daslda\r\n Prefersaasda reanreainrea";

int positionOfNewLine = s.IndexOf("\r\n");

if (positionOfNewLine >= 0)
{
    string partBefore = s.Substring(0, positionOfNewLine);
}

edited May 23 '22 at 23:19

John Smith

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answered Jan 09 '17 at 08:16

Patrick Hofman

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2

@Toshi: `s` was not a valid string, because of `\` after `\r\n`, now it will compile – sujith karivelil Jan 09 '17 at 08:21

Mohit S · Answer 2 · 2017-01-09T08:37:48.040

3

You can use Split like this

string mystring = @"lalal lalal laldlasdaa daslda\r\n\Prefersaasda reanreainrea";
string mylines = mystring.Split(new string[] { @"\r\n" }, StringSplitOptions.None)[0];

Whereas if the string is like

string mystring = "lalal lalal laldlasdaa daslda\r\n Prefersaasda reanreainrea";
string mylines = mystring.Split(new string[] { Environment.NewLine }, StringSplitOptions.None)[0];

Environment.NewLine will also work with it. The with \r\n\P is making that string an invalid string thus \r\n P makes it a new line

edited Jan 09 '17 at 08:37

answered Jan 09 '17 at 08:16

Mohit S

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Splitting is very expensive on long strings if you just want the first part. – Patrick Hofman Jan 09 '17 at 08:23
You are working with a broken string and thus your `@"\r\n"` is very wrong. It will take `\\` literally! **This will not work for the problem OP is facing.** – Patrick Hofman Jan 09 '17 at 08:29

score 3 · Answer 3 · answered Jan 09 '17 at 08:17

Hope that this is what you are looking for:

string inputStr = "lalal lalal laldlasdaa daslda\r\nPrefersaasda reanreainrea";
int newLineIndex =  inputStr.IndexOf("\r\n");
if(newLineIndex != -1)
{ 
  string outPutStr = inputStr.Substring(0, newLineIndex );
  // Continue
}
else
{
    // Display message no new line character 
}

Checkout an example here

Get the part of a string before new line symbol

3 Answers3