字符串长度
String str = "齐天大圣大闹天宫";
System.out.println(str.length());
获取指定位置的字符
System.out.println(str.charAt(0));
获取字符的位置
System.out.println(str.indexOf("大"));
截取字符串(左闭右开)
System.out.println(str.substring(2, 5));
字符串替换
System.out.println(str.replace("大", "小"));
字符串拼接
System.out.println("字符串拼接:");
String str1 = "hello";
String str2 = "world";
String str3 = str1 + str2;
System.out.println(str3);
String str10 = "hello";
String str11 = "world";
System.out.println(str10.concat(str11));
字符串分割
System.out.println("字符串分割:");
String str4 = "aaa,bbb,ccc";
String[] strArray = str4.split(",");
for (String s : strArray) {System.out.println(s);
}
去除空格
System.out.println("字符串去空格:");
String str5 = " hello world ";
System.out.println(str5.trim());
字符串大小写转换
System.out.println("字符串大小写转换:");
String str6 = "hello world";
System.out.println(str6.toUpperCase());
System.out.println(str6.toLowerCase());
字符串比较
System.out.println("字符串比较:");
String str7 = "hello";
String str8 = "world";
System.out.println(str7.equals(str8));
字符串格式化(模板字符串)
System.out.println("字符串格式化:");
String str12 = "hello";
String str13 = "world";
System.out.println(String.format("%s %s", str13,str12));
String template = "{}爱{}!{}";
String fin = StrUtil.format(template, "我", "JAVA","哈");
字符串转数组
System.out.println("字符串转数组:");
String str14 = "hello,world";
char[] strArray1 = str14.toCharArray();
for (char c : strArray1) {System.out.println(c);
}