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
Use:
String text = "jon skeet, miles o'brien, old mcdonald";
Pattern pattern = Pattern.compile("\\b([a-z])([\\w]*)");
Matcher matcher = pattern.matcher(text);
StringBuffer buffer = new StringBuffer();
while (matcher.find()) {
matcher.appendReplacement(buffer, matcher.group(1).toUpperCase() + matcher.group(2));
}
String capitalized = matcher.appendTail(buffer).toString();
System.out.println(capitalized);
其他回答
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);
最基本和最简单的理解方法(我认为):
import java.util.Scanner;
public class ToUpperCase {
static Scanner kb = new Scanner(System.in);
public static String capitalize(String str){
/* Changes 1st letter of every word
in a string to upper case
*/
String[] ss = str.split(" ");
StringBuilder[] sb = new StringBuilder[ss.length];
StringBuilder capped = new StringBuilder("");
str = "";
// Capitalise letters
for (int i = 0; i < ss.length; i++){
sb[i] = new StringBuilder(ss[i]); // Construct and assign
str += Character.toUpperCase(ss[i].charAt(0)); // Only caps
//======================================================//
// Replace 1st letters with cap letters
sb[i].setCharAt(0, str.charAt(i));
capped.append(sb[i].toString() + " "); // Formatting
}
return capped.toString();
}
public static void main(String[] args){
System.out.println(capitalize(kb.nextLine()));
}
}
如果你需要大写标题，这可能很有用。它将每个由" "分隔的子字符串大写，除了"a"或"the"之类的指定字符串。我还没有运行它，因为已经晚了，不过应该没问题。一次使用Apache Commons StringUtils.join()。如果你愿意，你可以用一个简单的循环来代替它。
private static String capitalize(String string) {
if (string == null) return null;
String[] wordArray = string.split(" "); // Split string to analyze word by word.
int i = 0;
lowercase:
for (String word : wordArray) {
if (word != wordArray[0]) { // First word always in capital
String [] lowercaseWords = {"a", "an", "as", "and", "although", "at", "because", "but", "by", "for", "in", "nor", "of", "on", "or", "so", "the", "to", "up", "yet"};
for (String word2 : lowercaseWords) {
if (word.equals(word2)) {
wordArray[i] = word;
i++;
continue lowercase;
}
}
}
char[] characterArray = word.toCharArray();
characterArray[0] = Character.toTitleCase(characterArray[0]);
wordArray[i] = new String(characterArray);
i++;
}
return StringUtils.join(wordArray, " "); // Re-join string
}
我使用wordUppercase(String s)从雨滴库。 因为这是我的库，这里只有一个方法
/**
* Set set first letter from every word uppercase.
*
* @param s - The String wich you want to convert.
* @return The string where is the first letter of every word uppercase.
*/
public static String wordUppercase(String s){
String[] words = s.split(" ");
for (int i = 0; i < words.length; i++) words[i] = words[i].substring(0, 1).toUpperCase() + words[i].substring(1).toLowerCase();
return String.join(" ", words);
}
希望能有所帮助。
public static String toTitleCase(String word){
return Character.toUpperCase(word.charAt(0)) + word.substring(1);
}
public static void main(String[] args){
String phrase = "this is to be title cased";
String[] splitPhrase = phrase.split(" ");
String result = "";
for(String word: splitPhrase){
result += toTitleCase(word) + " ";
}
System.out.println(result.trim());
}
