How to remove extra returns and spaces in a string by regex?

问题

I convert a HTML code to plain text.But there are many extra returns and spaces.How to remove them?

回答1:

I'm assuming that you want to

find two or more consecutive spaces and replace them with a single space, and
find two or more consecutive newlines and replace them with a single newline.

If that's correct, then you could use

resultString = Regex.Replace(subjectString, @"( |\r?\n)\1+", "$1");

This keeps the original "type" of whitespace intact and also preserves Windows line endings correctly. If you also want to "condense" multiple tabs into one, use

resultString = Regex.Replace(subjectString, @"( |\t|\r?\n)\1+", "$1");

To condense a string of newlines and spaces (any number of each) into a single newline, use

resultString = Regex.Replace(subjectString, @"(?:(?:\r?\n)+ +){2,}", @"\n");

回答2:

string new_string = Regex.Replace(orig_string, @"\s", "") will remove all whitespace

string new_string = Regex.Replace(orig_string, @"\s+", " ") will just collapse multiple whitespaces into one

回答3:

I used a lot of algorithm for that. Every loop was good but this was clear and absolute.

//define what you want to remove as char

char tb = (char)9; //Tab char ascii code
spc = (char)32;    //space char ascii code
nwln = (char)10;   //New line char ascii char

yourstring.Replace(tb,"");
yourstring.Replace(spc,"");
yourstring.Replace(nwln,"");

//by defining chars, result was better.

回答4:

You can use Trim() to remove the spaces and returns. In HTML the spaces is not important so you can omit them by using the Trim() method in System.String class.

来源：https://stackoverflow.com/questions/4973524/how-to-remove-extra-returns-and-spaces-in-a-string-by-regex

标签

regex

return

space