JavaScript Regular Expressions: finding numbers in strings

The morning master left me a task, let's think about how to use regular expressions, find numbers in strings, and replace numbers. The following code uses a regular expression to find a number in a string, replacing the original number with the twice-fold value of the found number using the Replace () method. The second parameter of the replace () method is a function that returns twice times the value of the found number.

<script>
    var str= "Last year was 2014, this year is 2015";
    var function  () {
        // This and arguments        are generated internally when the method is called Console.log (arguments[0]);
        // after you find a number, you can do other things        with the number return arguments[0] * 2;    });
    Console.log (NEWSTR);

</script>

Regular expression/\d+/g: matches at least one number.

Arguments,console.log (arguments) is generated internally when the function is called; The result:

The numbers 2014 and 2015 need to be obtained, so just get arguments[0].

Console.log (Arguments[0]); The result:

The final result is: "Last year was 4028, this year is 4030"

After you find a number, you can also do other things with numbers

JavaScript Regular Expressions: finding numbers in strings