How does Task int become an int

Question

We have this method   async Task lt int gt  AccessTheWebAsync          HttpClient client   new HttpClient        Task lt string gt  getStringTask   client GetStringAsync  http   msdn microsoft com           You can do work here that doesn t rely on the string from GetStringAsync     DoIndependentWork        string urlContents   await getStringTask       The thing is that this returns an int to a method that has a return type of Task lt int gt     return urlContents Length      Does an implicit conversion occur between Task lt int gt  and int  If not  then what is happening   How is it implemented to work

User · Answer

No requires converting the Task to int  Simply Use The Task Result   int taskResult   AccessTheWebAndDouble   Result   public async Task lt int gt  AccessTheWebAndDouble         int task   AccessTheWeb        return task      It will return the value if available otherwise it return 0

User · Answer

Does an implicit conversion occur between Task lt   and int    Nope  This is just part of how async await works   Any method declared as async has to have a return type of    void  avoid if possible  Task  no result beyond notification of completion failure  Task lt T gt   for a logical result of type T in an async manner    The compiler does all the appropriate wrapping  The point is that you re asynchronously returning urlContents Length - you can t make the method just return int  as the actual method will return when it hits the first await expression which hasn t already completed  So instead  it returns a Task lt int gt  which will complete when the async method itself completes   Note that await does the opposite - it unwraps a Task lt T gt  to a T value  which is how this line works   string urlContents   await getStringTask        but of course it unwraps it asynchronously  whereas just using Result would block until the task had completed   await can unwrap other types which implement the awaitable pattern  but Task lt T gt  is the one you re likely to use most often    This dual wrapping unwrapping is what allows async to be so composable  For example  I could write another async method which calls yours and doubles the result   public async Task lt int gt  AccessTheWebAndDoubleAsync         var task   AccessTheWebAsync        int result   await task      return result   2       Or simply return await AccessTheWebAsync     2  of course

[c#] How does Task<int> become an int?

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