Exists

Ensures the value is exists in database GET, POST method is allowed for rmote validation. default method is GET.

#Directive Code Snippet

<!DOCTYPE html> 
<html lang="en"> 
    ...
    <form (ngSubmit)="onSubmit(form)" #form="ngForm">
		<input [exists]="{url:<API_URL>,method:<method>}" type="text" name="<name>" [(ngModel)]="<name>" #<name>="ngModel">
	</form>
    ...
</html>

#Config Options:

Property	Type	Required	Description
`url`	`string`	Yes	The endpoint URL to which the HTTP request will be sent.
`field`	`string`	No	The specific field/property name to be used or mapped from the response. by default it will be the form name
`request`	`object`	No	The request body/payload to be sent with the HTTP call. Typically used with `POST` requests.
`params`	`object`	No	Query parameters to be appended to the URL (used with `GET` requests or additional filters).
`method`	`'GET' \| 'POST'`	No	The HTTP method to use for the request. Defaults to `'GET'` if not specified.