[Solved] IQueryable does not contain definition for GetAwaiter
I’m using WebAPI in entity framework to create a new endpoint and I am having some issues. I’m trying to use a Linq Where statement to get my data, but I’m receiving the following error.
‘IQueryable’ does not contain a definition for ‘GetAwaiter’ and
no extension method ‘GetAwaiter’ accepting a first argument of type
‘IQueryable’ could be found (are you missing a using directive
or an assembly reference?)
Here is my code.
[ResponseType(typeof(Vocab))]
public async Task<IHttpActionResult> GetVocabByLesson(int lessonId)
{
Vocab vocab = await db.Vocabs.Where(a => a.LessonId == lessonId);
if (vocab == null)
return NotFound();
return Ok(vocab);
}
Solution #1:
Use FirstOrDefaultAsync extension method:
[ResponseType(typeof(Vocab))]
public async Task<IHttpActionResult> GetVocabByLesson(int lessonId)
{
Vocab vocab = await db.Vocabs.FirstOrDefaultAsync(a => a.LessonId == lessonId);
if (vocab == null)
return NotFound();
return Ok(vocab);
}
By your code I can deduct you want to return just an element, that’s why I have suggested to use FirstOrDefaultAsync. But in case you want to get more than one element that meets some condition then use ToListAsync:
[ResponseType(typeof(Vocab))]
public async Task<IHttpActionResult> GetVocabByLesson(int lessonId)
{
var result= await db.Vocabs.Where(a => a.LessonId == lessonId).ToListAsync();
if (!result.Any())
return NotFound();
return Ok(result);
}
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