How to eliminate ALL line breaks in string?

问题:

I have a need to get rid of all line breaks that appear in my strings (coming from db). I do it using code below:

value.Replace("\r\n", "").Replace("\n", "").Replace("\r", "")

I can see that there's at least one character acting like line ending that survived it. The char code is 8232.

It's very lame of me, but I must say this is the first time I have a pleasure of seeing this char. It's obvious that I can just replace this char directly, but I was thinking about extending my current approach (based on replacing combinations of "\r" and "\n") to something much more solid, so it would not only include the '8232' char but also all others not-found-by-me yet.

Do you have a bullet-proof approach for such a problem?

EDIT#1:

It seems to me that there are several possible solutions:

1. use Regex.Replace
2. remove all chars if it's IsSeparator or IsControl
3. replace with " " if it's IsWhiteSpace
4. create a list of all possible line endings ( "\r\n", "\r", "\n",LF ,VT, FF, CR, CR+LF, NEL, LS, PS) and just replace them with empty string. It's a lot of replaces.

I would say that the best results will be after applying 1st and 4th approaches but I cannot decide which will be faster. Which one do you think is the most complete one?

EDIT#2

I posted anwer below.

回答1:

Below is the extension method solving my problem. LineSeparator and ParagraphEnding can be of course defined somewhere else, as static values etc.

public static string RemoveLineEndings(this string value)
{
    if(String.IsNullOrEmpty(value))
    {
        return value;
    }
    string lineSeparator = ((char) 0x2028).ToString();
    string paragraphSeparator = ((char)0x2029).ToString();

    return value.Replace("\r\n", string.Empty)
                .Replace("\n", string.Empty)
                .Replace("\r", string.Empty)
                .Replace(lineSeparator, string.Empty)
                .Replace(paragraphSeparator, string.Empty);
}

回答2:

According to wikipedia, there are numerous line terminators you may need to handle (including this one you mention).

LF: Line Feed, U+000A
VT: Vertical Tab, U+000B
FF: Form Feed, U+000C
CR: Carriage Return, U+000D
CR+LF: CR (U+000D) followed by LF (U+000A)
NEL: Next Line, U+0085
LS: Line Separator, U+2028
PS: Paragraph Separator, U+2029

回答3:

8232 (0x2028) and 8233 (0x2029) are the only other ones you might want to eliminate. See the documentation for char.IsSeparator.

回答4:

Props to Yossarian on this one, I think he's right. Replace all whitespace with a single space:

data = Regex.Replace(data, @"\s+", " ");

回答5:

I'd recommend removing ALL the whitespace (char.IsWhitespace), and replacing it with single space.. IsWhiteSpace takes care of all weird unicode whitespaces.

回答6:

This is my first attempt at this, but I think this will do what you want....

var controlChars = from c in value.ToCharArray() where Char.IsControl(c) select c;
foreach (char c in controlChars)  
   value = value.Replace(c.ToString(), "");

Also, see this link for details on other methods you can use: Char Methods

回答7:

Have you tried string.Replace(Environment.NewLine, "") ? That usually gets a lot of them for me.

回答8:

Check out this link: http://msdn.microsoft.com/en-us/library/844skk0h.aspx

You wil lhave to play around and build a REGEX expression that works for you. But here's the skeleton...

static void Main(string[] args)
{

        StringBuilder txt = new StringBuilder();
        txt.Append("Hello \n\n\r\t\t");
        txt.Append( Convert.ToChar(8232));

        System.Console.WriteLine("Original: <" + txt.ToString() + ">");

        System.Console.WriteLine("Cleaned: <" + CleanInput(txt.ToString()) + ">");

        System.Console.Read();

    }

    static string CleanInput(string strIn)
    {
        // Replace invalid characters with empty strings.
        return Regex.Replace(strIn, @"[^\w\.@-]", ""); 
    }

回答9:

Assuming that 8232 is unicode, you can do this:

value.Replace("\u2028", string.Empty);

回答10:

personally i'd go with

    public static String RemoveLineEndings(this String text)
    {
        StringBuilder newText = new StringBuilder();
        for (int i = 0; i < text.Length; i++)
        {
            if (!char.IsControl(text, i))
                newText.Append(text[i]);
        }
        return newText.ToString();
    }

回答11:

If you've a string say "theString" then use the method Replace and give it the arguments shown below:

theString = theString.Replace(System.Environment.NewLine, "");

回答12:

Here are some quick solutions with .NET regex:

• To remove any whitespace from a string: s = Regex.Replace(s, @"\s+", ""); (\s matches any Unicode whitespace chars)
• To remove all whitespace BUT CR and LF: s = Regex.Replace(s, @"[\s-[\r\n]]+", ""); ([\s-[\r\n]] is a character class containing a subtraction construct, it matches any whitespace but CR and LF)
• To remove any vertical whitespace, subtract \p{Zs} (any horizontal whitespace but tab) and \t (tab) from \s: s = Regex.Replace(s, @"[\s-[\p{Zs}\t]]+", "");.

Wrapping the last one into an extension method:

public static string RemoveLineEndings(this string value)
{
    return Regex.Replace(value, @"[\s-[\p{Zs}\t]]+", "");
}

See the regex demo.