正则表达式匹配字母数字和空格

Question

What am I doing wrong here?

string q = "john s!";
string clean = Regex.Replace(q, @"([^a-zA-Z0-9]|^\s)", string.Empty);
// clean == "johns". I want "john s";

Answer 1

just a FYI

string clean = Regex.Replace(q, @"[^a-zA-Z0-9\s]", string.Empty);

would actually be better like

string clean = Regex.Replace(q, @"[^\w\s]", string.Empty);

Answer 2

This:

string clean = Regex.Replace(dirty, "[^a-zA-Z0-9\x20]", String.Empty);

\\x20 is ascii hex for 'space' character

you can add more individual characters that you want to be allowed. If you want for example "?" to be ok in the return string add \\x3f .

Answer 3

I got it:

string clean = Regex.Replace(q, @"[^a-zA-Z0-9\s]", string.Empty);

Didn't know you could put \\s in the brackets

Answer 4

I suspect ^ doesn't work the way you think it does outside of a character class.

What you're telling it to do is replace everything that isn't an alphanumeric with an empty string, OR any leading space. I think what you mean to say is that spaces are ok to not replace - try moving the \\s into the [] class.

Answer 5

The following regex is for space inclusion in textbox.

Regex r = new Regex("^[a-zA-Z\\s]+");
r.IsMatch(textbox1.text);

This works fine for me.

Answer 6

There appear to be two problems.

1. You're using the ^ outside a [] which matches the start of the line
2. You're not using a * or + which means you will only match a single character.

I think you want the following regex @"([^a-zA-Z0-9\\s])+"

Answer 7

bottom regex with space, supports all keyboard letters from different culture

 string input = "78-selim güzel667.,?";
 Regex regex = new Regex(@"[^\w\x20]|[\d]");
 var result= regex.Replace(input,"");
 //selim güzel

Answer 8

The circumflex inside the square brackets means all characters except the subsequent range. You want a circumflex outside of square brackets.