Java中是否内置了一个函数,使字符串中每个单词的第一个字符大写,而不影响其他字符?

例子:

乔恩·斯基特->乔恩·斯基特 miles o'Brien -> miles o'Brien (B仍然是大写,这排除了Title Case) 老麦当劳->

*(老麦当劳也会被发现,但我不指望它有那么聪明。)

快速浏览一下Java字符串文档就会发现只有toUpperCase()和toLowerCase(),它们当然没有提供所需的行为。当然,谷歌的结果主要是这两个函数。它看起来像一个已经被发明出来的轮子,所以问一下也无妨,这样我以后就可以用它了。


当前回答

    s.toLowerCase().trim();
    result += Character.toUpperCase(s.charAt(0));
    result += s.substring(1, s.indexOf(" ") + 1);
    s = s.substring(s.indexOf(" ") + 1);

    do {
        if (s.contains(" ")) {
            result += " ";
            result += Character.toUpperCase(s.charAt(0));
            result += s.substring(1, s.indexOf(" "));
            s = s.substring(s.indexOf(" ") + 1);
        } else {
            result += " ";
            result += Character.toUpperCase(s.charAt(0));
            result += s.substring(1);
            break;
        }
    } while (true);
    System.out.println(result);

其他回答

worddutil .capitalize(str) (from apache common -text)

(注意:如果你需要“fOO BAr”变成“fOO BAr”,那么用大写的(..)代替)

String toUpperCaseFirstLetterOnly(String str) {
    String[] words = str.split(" ");
    StringBuilder ret = new StringBuilder();
    for(int i = 0; i < words.length; i++) {
        ret.append(Character.toUpperCase(words[i].charAt(0)));
        ret.append(words[i].substring(1));
        if(i < words.length - 1) {
            ret.append(' ');
        }
    }
    return ret.toString();
}

我只想通过仅使用Java代码为该问题添加一个替代解决方案。 没有额外的库

public String Capitalize(String str) {

            String tt = "";
            String tempString = "";
            String tempName = str.trim().toLowerCase();
            String[] tempNameArr = tempName.split(" ");
            System.out.println("The size is " + tempNameArr.length);
            if (tempNameArr.length > 1) {
                for (String t : tempNameArr) {
                    tt += Capitalize(t);
                    tt += " ";
                }
                tempString  = tt;
            } else {
                tempString = tempName.replaceFirst(String.valueOf(tempName.charAt(0)), String.valueOf(tempName.charAt(0)).toUpperCase());
            }
            return tempString.trim();
        }

下面是这个问题的Kotlin版本:

fun capitalizeFirstLetterOfEveryWord(text: String): String
{
    if (text.isEmpty() || text.isBlank())
    {
        return ""
    }

    if (text.length == 1)
    {
        return Character.toUpperCase(text[0]).toString()
    }

    val textArray = text.split(" ")
    val stringBuilder = StringBuilder()

    for ((index, item) in textArray.withIndex())
    {
        // If item is empty string, continue to next item
        if (item.isEmpty())
        {
            continue
        }

        stringBuilder
            .append(Character.toUpperCase(item[0]))

        // If the item has only one character then continue to next item because we have already capitalized it.
        if (item.length == 1)
        {
            continue
        }

        for (i in 1 until item.length)
        {
            stringBuilder
                .append(Character.toLowerCase(item[i]))
        }

        if (index < textArray.lastIndex)
        {
            stringBuilder
                .append(" ")
        }
    }

    return stringBuilder.toString()
}

这是我做的另一种方法

    StringBuilder str=new StringBuilder("pirai sudie test test");

    str.setCharAt(0,Character.toUpperCase(str.charAt(0)));

    for(int i=str.length()-1;i>=0;i--)
    {
        if(Character.isSpaceChar(str.charAt(i)))
            str.setCharAt(i+1,Character.toUpperCase(str.charAt(i+1)));
    }

    System.out.println(str);