java字串大小寫字母互改，java字串大小寫

java字串大小寫字母互改，java字串大小寫

import java.util.Scanner;public class Test {    /**     * 測試資料     *      * @param args     */    public static void main(String[] args) {        Scanner sc = new Scanner(System.in);        String s = sc.nextLine();        System.out.println(ExchangeStringA(s));        System.out.println(ExchangeStringB(s));    }    /**     * 方式一     *      * @param s     * @return     */    public static String ExchangeStringA(String s) {        StringBuffer result = new StringBuffer();        String lowerString = s.toLowerCase();    //這兩步        String upString = s.toUpperCase();        //是關鍵        for (int i = 0; i < s.length(); i++) {            if (s.charAt(i) == lowerString.charAt(i)) {                result.append(upString.charAt(i));            } else {                result.append(lowerString.charAt(i));            }        }        return result.toString();    }    /**     * 方式二 以字母的ascii碼來操作 大小寫之間相差32      * a-z：97-122      * A-Z：65-90     * @param s     * @return     */    public static String ExchangeStringB(String s) {        char c[] = s.toCharArray();        for (int i = 0; i < c.length; i++) {            if (c[i] >= 65 && c[i] <= 90) {                c[i] = (char) (c[i] + 32);            } else {                c[i] = (char) (c[i] - 32);            }        }        return String.valueOf(c);    }}