String类中方法的记录

替换方法: replaceAll;

        搭配正则表达式获取对应的内容

String str = "Z001";
String prefix = str.replaceAll("[^A-Za-z]", "");
System.out.println("prefix = " + prefix); // Z

String num = str.replaceAll("[^0-9]", "");
System.out.println("num = " + num ); // 001

System.out.println("Number = " + Integer.parseInt(num)); // 1

格式化方法:format

int beginNum = 5;
// beginNum = 000005
System.out.println("beginNum = " + String.format("%0" + 6 + "d", beginNum));