String类中的方法总结。

package day01.arr;

public class Demo15 {
public static void main(String[] args) {
/*
* 字符串与字符数组的转化
*/
String ss = "HELLO";
char c[] = ss.toCharArray();
for (char d : c) {
System.out.print(d + " ");
}
/*
* 字符数组转换成字符串
*/
String string = new String(c);
String string2 = new String(c, 0, 3);
System.out.println(string);
System.out.println(string2);
/*
* 取出字符串中指定字符
*/
String str = "hello,word";
System.out.println(str.charAt(4));
/*
* 字符串转换为byte数组
*/
String string3 = "637329,123";
byte b[] = string3.getBytes();
for (byte d : b) {
System.out.println(d);
}
/*
* byte数组转换为字符串
*/
String string4 = new String(b);
String string5 = new String(b, 0, 4);
System.out.println(string4 + "==" + string5);
/*
* 取得一个字符串的长度
*/
String string6 = "hello,word";
System.out.println(string6.length());
/*
* 查找一个指定的字符串是否存在
*/
String string7 = "hello,wangfeng";
System.out.println(string7.indexOf("f"));
System.out.println(string7.indexOf("w",7 ));
/*
* 去掉左右空格
*/
String string8 = " wangfeng ";
System.out.println(string8.trim());
/*
* 字符串截取
*/
String string9 = "wgfkhosng附近的说法";
System.out.println(string9.substring(1, 3));
System.out.println(string9.substring(2));
/*
* 字符串大小写转换
*/
String string10 = "WWFENGxi";
System.out.println(string10.toUpperCase());
System.out.println(string10.toLowerCase());
/*
* 判断字符串是以哪个字符开始的
*/
String string11 = "wang feng";
System.out.println(string11.startsWith("w"));
System.out.println(string11.endsWith("n"));
/*
* 不区分大小写对比
*/
String string12 = "hello word";
String string13 = "HELLO WORD";
System.out.println(string12.equalsIgnoreCase(string13));
/*
* 将一个指定的字符串替换成其他的字符串
*/
String string14 = "hhaa";
String string15 = "woshishei";
System.out.println(string14.replaceAll("h", string15));
}
}