Is there a CapitalizeFirstLetter method?

Question

Is there a method to do that? Could it be done with an extension method?

I want to achieve this:

string s = "foo".CapitalizeFirstLetter();
// s is now "Foo"

score 19 · Accepted Answer · edited May 23 '17 at 11:48

19

A simple extension method, that will capitalize the first letter of a string. As Karl pointed out, this assumes that the first letter is the right one to change and is therefore not perfectly culture-safe.

public static string CapitalizeFirstLetter(this String input)
{
    if (string.IsNullOrEmpty(input)) 
        return input;

    return input.Substring(0, 1).ToUpper(CultureInfo.CurrentCulture) +
        input.Substring(1, input.Length - 1);
}

You can also use System.Globalization.CultureInfo.CurrentCulture.TextInfo.ToTitleCase. The function will convert the first character of each word to upper case. So if your input string is have fun the result will be Have Fun.

public static string CapitalizeFirstLetter(this String input)
{
     if (string.IsNullOrEmpty(input)) 
         return input;

     return CultureInfo.CurrentCulture.TextInfo.ToTitleCase(input);
}

See this question for more information.

edited May 23 '17 at 11:48

Community

1
1

answered Apr 14 '09 at 16:39

xsl

17,116
18
71
112

Thanks, I don't know why I didn't find it searching – juan Apr 14 '09 at 16:41
1

This still assumes that the first letter is the right one to change. Not perfectly culture-safe yet. – Karl Apr 14 '09 at 16:50
first example will throw an exception if the string length is zero. Should add "if (string.IsNullOrEmpty(input)) return input;" at the top. – Michael Meadows Apr 14 '09 at 17:27
Thank you, added it to the post. – xsl Apr 14 '09 at 21:21
1

Just one note: The CultureInfo.CurrentCulture.TextInfo.ToTitleCase(input); will not work if the all letters in text are in uppercase, – Paulo Dinis Mar 17 '16 at 16:26

score 10 · Answer 2 · answered Apr 14 '09 at 16:44

10

System.Globalization.CultureInfo.CurrentCulture.TextInfo.ToTitleCase

It has the advantage of being culture-safe.

answered Apr 14 '09 at 16:44

Chris

27,596
25
124
225

After reading the remarks in the MSDN docs, it turns out this method just changes first letters to uppercase regardless of any real cultural details anyway. +1 for pointing out obscure framework method, -1 for the specified method being misleading/broken. – ScottS Apr 14 '09 at 16:52
1

Well the optimist would say that if you use it now, it may actually function as expected in the future. At any rate, it does exactly what was requested, and is built into the framework :P – Chris Apr 14 '09 at 17:29

score 0 · Answer 3 · answered Aug 15 '12 at 17:41

0

Try this:

static public string UpperCaseFirstCharacter(this string text) {
    return Regex.Replace(text, "^[a-z]", m => m.Value.ToUpper());
}

answered Aug 15 '12 at 17:41

JoelFan

37,465
35
132
205

score 0 · Answer 4 · answered Apr 06 '22 at 13:33

In my case the text input can also be all in capitals.

I added a ToLower before the ToTitleCase is done:

    public static string CapitalizeFirstLetter(this string input)
    {
        if (string.IsNullOrWhiteSpace(input))
        {
            return input;
        }

        return CultureInfo.CurrentCulture.TextInfo.ToTitleCase(input.ToLower(CultureInfo.CurrentCulture));
    }

Is there a CapitalizeFirstLetter method?

4 Answers4