Doing Operations on C# Async Method Result

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I am working on converting some synchronous code to async in C# (.NET 4.5). I have a senario where I need to do an operation using the number of models retrieved by a remote query as an input.

An example of the desired behavior:

public async Task<List<Model>> GetEntityModelsAsync()
{
    return // some models from a database async
}

public async Task<int> DoSomeWorkWithModelCount() 
{
    Task<IEnumerable<Model>> models = GetEntityModelsAsync();

    // some other code to execute before awaiting

    int count = await models.Count();

    // do more work and return result
}

The above code will not compile with the error 'Task<IEnumerable>' does not contain a definition for 'Count'...

I assume this is because the type of the variable is 'Task<IEnumerable>'. Is there any way to extract the result from the task and do operations that are allowed on its type?

I have tried getting the result in this way:

int count = await models.Result.Count(); // error: 'int' does not contain a definition for 'GetAwaiter'

await recentApplications.GetAwaiter().GetResult(); // error: 'int' does not contain a definition for 'GetAwaiter'

Am I forced to first await the result into another variable like this:

IEnumerable<Model> modelsResult = await models;
int count = modelsResult.Count();

Or is there a more streamlined way to do type operations on the results of awaited tasks?

async-await .net c#
2 Answers

This is what you do if you want it in one line:

int count = (await models).Count();
user_140191500

Use

int count = await models.CountAsync();
user_81950760
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