试试这个:

string myText = "a Simple string";

string asTitleCase =
    System.Threading.Thread.CurrentThread.CurrentCulture.TextInfo.
    ToTitleCase(myText.ToLower());

如前所述，使用TextInfo。ToTitleCase可能不会给您想要的确切结果。如果你需要更多的输出控制，你可以这样做:

IEnumerable<char> CharsToTitleCase(string s)
{
    bool newWord = true;
    foreach(char c in s)
    {
        if(newWord) { yield return Char.ToUpper(c); newWord = false; }
        else yield return Char.ToLower(c);
        if(c==' ') newWord = true;
    }
}

然后像这样使用它:

var asTitleCase = new string( CharsToTitleCase(myText).ToArray() );

MSDN: TextInfo。ToTitleCase

确保你包括:使用系统。全球化

string title = "war and peace";

TextInfo textInfo = new CultureInfo("en-US", false).TextInfo;

title = textInfo.ToTitleCase(title); 
Console.WriteLine(title) ; //War And Peace

//When text is ALL UPPERCASE...
title = "WAR AND PEACE" ;

title = textInfo.ToTitleCase(title); 
Console.WriteLine(title) ; //WAR AND PEACE

//You need to call ToLower to make it work
title = textInfo.ToTitleCase(title.ToLower()); 
Console.WriteLine(title) ; //War And Peace

首先使用ToLower()，然后对结果使用CultureInfo.CurrentCulture.TextInfo.ToTitleCase以获得正确的输出。

    //---------------------------------------------------------------
    // Get title case of a string (every word with leading upper case,
    //                             the rest is lower case)
    //    i.e: ABCD EFG -> Abcd Efg,
    //         john doe -> John Doe,
    //         miXEd CaSING - > Mixed Casing
    //---------------------------------------------------------------
    public static string ToTitleCase(string str)
    {
        return CultureInfo.CurrentCulture.TextInfo.ToTitleCase(str.ToLower());
    }

public static string PropCase(string strText)
{
    return new CultureInfo("en").TextInfo.ToTitleCase(strText.ToLower());
}

如果有人对Compact Framework的解决方案感兴趣:

return String.Join(" ", thestring.Split(' ').Select(i => i.Substring(0, 1).ToUpper() + i.Substring(1).ToLower()).ToArray());

最好通过尝试自己的代码来理解…

阅读更多

http://www.stupidcodes.com/2014/04/convert-string-to-uppercase-proper-case.html

1)将字符串转换为大写

string lower = "converted from lowercase";
Console.WriteLine(lower.ToUpper());

2)将字符串转换为小写

string upper = "CONVERTED FROM UPPERCASE";
Console.WriteLine(upper.ToLower());

3)转换String为TitleCase

    CultureInfo cultureInfo = Thread.CurrentThread.CurrentCulture;
    TextInfo textInfo = cultureInfo.TextInfo;
    string txt = textInfo.ToTitleCase(TextBox1.Text());