regex match all digits in string code example

Example 1: get only numbers regex javascript

var numberPattern = /\d+/g;

'something102asdfkj1948948'.match( numberPattern )

Example 2: regex match any number of digits

For matching an integer number of one single char/digit, specify:
[0-9]
But for matching any number of more than one char/digit; add "+":
[0-9]+
Example for matching hour with minutes of HH:MM format in a file:
grep "[0-9]\+\:[0-9]\+" file.txt