Check if string contains only numeric
Given a string, check if the string contains only numeric characters ( from 0 to 9), using JavaScript.
Solution
To check if given string str
contains only numeric characters using JavaScript, call match()
method on the given string and pass a regular expression that matches one or more numeric characters /^[0-9]+$/
as argument to the method.
str.match(/^[0-9]+$/)
The match()
method returns true
if the given string str
contains only numeric, or false
otherwise. We can use this expression as a condition in if-else statement.
Programs
1. Given a string str
. Check if this string contains only numeric.
var str = '01245124512';
if ( str.match(/^[0-9]+$/) ) {
console.log('string contains only numeric');
} else {
console.log('string does not contain only numeric');
}
Since the string contains only numeric, if-block must run.
2. Given a string str
. This string does contain some alphabets. Check programmatically if this string contains only numeric.
var str = '125412am8';
if ( str.match(/^[A-Za-z0-9]+$/) ) {
console.log('string contains only alphanumeric');
} else {
console.log('string does not contain only alphanumeric');
}
Since the string does not contain only numeric, else-block must run.