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How to convert Func to Predicate?

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离开以前 2020-12-01 12:34

Yes I\'ve seen this but I couldn\'t find the answer to my specific question.

Given a lambda testLambda that takes T and returns a boolean (I can mak

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  • 刺人心
    刺人心 (楼主)
    2020-12-01 12:55

    Easy:

    Func func = x => x.Length > 5;
Predicate predicate = new Predicate(func);

    Basically you can create a new delegate instance with any compatible existing instance. This also supports variance (co- and contra-):

    Action actOnObject = x => Console.WriteLine(x);
Action actOnString = new Action(actOnObject);

Func returnsString = () => "hi";
Func returnsObject = new Func(returnsString);



    If you want to make it generic:
    


    static Predicate ConvertToPredicate(Func func)
{
    return new Predicate(func);
}

    
    
    
             
    
                                                        
    
            
            
    
              
                
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