# OfflineEffect

Show an warning message when offline and prevent requests being sent:

```typescript
import { Injectable } from '@angular/core';
import { HttpRequest } from '@angular/common/http';
import { ObserveBeforeEffect } from 'ngx-crud';

import { NotifierService } from './notifier.service';

@Injectable()
export class OfflineEffect implements ObserveBeforeEffect
{
	constructor(protected notifierService : NotifierService) {}

	before<T>(request : HttpRequest<T>) : HttpRequest<T>
	{
		if (navigator.onLine)
		{
			return request;
		}
		notifierService.warning('OFFLINE_MODE');
	}
}
```


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