credentials_valid()
public function credentials_valid(string $identifier): string|bool
Description
Validation callback used during login form submission. Checks whether the submitted identifier (username or email) corresponds to an existing, non-blocked user account in the configured target table.
Parameters
| Parameter | Type | Description | Default | Required |
|---|---|---|---|---|
| identifier | string | The submitted username or email value to validate. | N/A | Yes |
Return Value
| Type | Description |
|---|---|
| string|bool | Returns true if the identifier is valid, or an error string if validation fails. |