How to determine if a string is a number

Source: Internet
Author: User

Determine if a string is a number?

Method One:

* Used to verify that the obtained string is not a number
* @param str
* @return
public static Boolean isnumeric (String str) {
for (int i = 0; i < str.length (); i++) {
Verifies that a character in a string is not a number
if (! Character.isdigit (Str.charat (i))) {
return false;
return true;

Method Two:

Determines whether the month is empty or is not a number, regular expressions
public static Boolean isvaild (String s) {
Pattern pattern = Pattern.compile ("[0-9]*");
Matcher Isnum = Pattern.matcher (s);

if (s! = null && isnum.matches ()) {
return true;
return false;

Take it, ~o (∩_∩) o~

How to determine if a string is a number

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