两种方法
利用String提供的常规API方法,效率较低巧用ASCII编码进行转换,效率较高,经测试,差不多是第一种的10倍
// 低效率public String toUpperFirstChar1(String string) {if (string == null || string.length() == 0) return string;if (string.charAt(0) >= 'a' && string.charAt(0) <= 'z') {String s = string.substring(0, 1).toUpperCase();return s + string.substring(1);}return string;}// 高效率public String toUpperFirstChar2(String string) {char[] chars = string.toCharArray();if (chars[0] >= 'a' && chars[0] <= 'z') {chars[0] -= 32;return String.valueOf(chars);}return string;}