How to get all value of invalid characters in a string in jquery?

Question

I have a jquery method that check special character as shown below:

function checkForSpecialChar(val) {

    if (val != 0 && /^[a-zA-Z0-9- ]*$/.test(val) == false) {

        return false;
    }

return true;
}

This is working fine as it validate the value correctly.

However now I need to get all invalid characters for the val string and show it to the user.

So for example if val is = 123gdf$£! It should get only the invalid character which is $£!.

Any idea how i can do that please?

Thanks in advance for any help.

Justinas · Accepted Answer · 2016-08-12 08:01:37Z

2

Just invert your regex by adding ^ inside []

[^a-zA-Z0-9- ] // match anything that is not alphanumerical, `-` or whitespace

alert(
  'Invalid characters of "123gdf$£!": '
  + (
    '123gdf$£!'.match(/[^a-zA-Z0-9- ]/g)
      .join('')
  )
);

answered Aug 12, 2016 at 8:01

Justinas

43.8k5 gold badges72 silver badges108 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Sachin Aryal · Accepted Answer · 2016-08-12 08:17:17Z

0

Try this

var val = "123gdf$£!".replace(new RegExp("[0-9a-zA-Z]", "g"), "");

answered Aug 12, 2016 at 8:17

Sachin Aryal

80116 silver badges36 bronze badges

Archit · Accepted Answer · 2016-08-12 08:29:35Z

0

Simply you can use string match() method of javascript.

Here it is:

var val= "123gdf$£!";
var result= str.match(/^[a-zA-Z0-9- ]*$/);

result will be an array with values.

answered Aug 12, 2016 at 8:29

Archit

1491 gold badge2 silver badges8 bronze badges