How to implement java string formatting and add 0 if the length is insufficient
You can fill in the number of digits with one line of code, but if you can fill in the number of digits with one line of code, you need to fill in spaces in front of it, and if you want to fill in 0, you need an integer type, use The function you get is String.format, which can format integers, strings, dates, etc.
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For example:
System.out.println(String.format(“%09d”, 123);
Output: 000000123
System.out.println(String.format(“%9s”, “123″);
Output: 123
The code is as follows:
System.out.println(String.format(“%09d”, Long.parseLong(“123″)));
Output: 000000123
The example code is as follows:
public static String addZeroForNum(String str, int strLength) {
int strLen = str.length();
if (strLen < strLength) {
while (strLen < strLength) {
StringBuffer sb = new StringBuffer();
sb.append("0").append(str);// 左补0
// sb.append(str).append("0");//右补0
str = sb.toString();
strLen = str.length();
}
}
return str;
}Recommended java related article tutorials: java quick start
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