What is Predicate Delegate in C#?

Category: C SharpWhat is Predicate Delegate in C#?
Editor">Editor Staff asked 2 years ago

What is Predicate Delegate in C#?

1 Answers
Editor">Editor Staff answered 2 years ago

Predicate is the delegate like Func and Action delegates. It represents a method containing a set of criteria and checks whether the passed parameter meets those criteria. A predicate delegate methods must take one input parameter and return a boolean – true or false.
The Predicate delegate is defined in the System namespace, as shown below:
Predicate signature: public delegate bool Predicate<in T>(T obj);
Same as other delegate types, Predicate can also be used with any method, anonymous method, or lambda expression.

Example: Predicate delegate

static bool IsUpperCase(string str)
{
    return str.Equals(str.ToUpper());
}

static void Main(string[] args)
{
    Predicate<string> isUpper = IsUpperCase;

    bool result = isUpper("hello world!!");

    Console.WriteLine(result);
}

 

Output:
false