## Input character validation

The `match` property defines a regular expression for checking the validity of entered characters.

**Possible values:**

- `RegExp` — regular expression (default `/[0-9]/`)
- `string` — string converted to regular expression

Checks each character during input. Characters that don't match the expression are ignored. Local `match` in group settings (`special[group].match`) takes priority over global. Differs from `pattern` in that `match` is a simple regular expression check, while `pattern` can be a function with access to mask state.

```html
<!-- Digits only (default) -->
<Mask mask="***-***" />

<!-- HEX characters -->
<Mask mask="***-***" :match="/[A-F0-9]/i" />

<!-- Different rules for groups -->
<Mask
  mask="***-###"
  match="\\d"
  :special="{
    '*': {},
    '#': { match: /[A-Z]/ }
  }"
/>
```
