Func is a family of delegate types in the .Net framework.
Func is a family of delegate types in the .net framework. They are in the System namespace and can be used to represent a function that returns a value and has zero or more parameters.
Questions tagged [func]
1154 questions
863
votes
3 answers
Func vs. Action vs. Predicate
With real examples and their use, can someone please help me understand:
When do we need a Func delegate?
When do we need an Action delegate?
When do we need a Predicate delegate?
InfoLearner
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238
votes
14 answers
"undefined" function declared in another file?
I'm trying to write a basic go program that calls a function on a different file, but a part of the same package. However, it returns:
undefined: NewEmployee
Here is the source code:
main.go:
package main
func main() {
emp := NewEmployee() …
Juan M
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231
votes
4 answers
Why Func instead of Predicate?
This is just a curiosity question I was wondering if anyone had a good answer to:
In the .NET Framework Class Library we have for example these two methods:
public static IQueryable Where(
this IQueryable source,
…
Svish
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199
votes
4 answers
Func with out parameter
Can I pass a method with an out parameter as a Func?
public IList FindForBar(string bar, out int count) { }
// somewhere else
public IList Find(Func> listFunction) { }
Func needs a type so out won't compile there, and…
blu
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159
votes
10 answers
Delegates: Predicate vs. Action vs. Func
Can someone provide a good explanation (hopefully with examples) of these 3 most important delegates:
Predicate
Action
Func
Sasha
142
votes
9 answers
converting a .net Func to a .net Expression>
Going from a lambda to an Expression is easy using a method call...
public void GimmeExpression(Expression> expression)
{
((MemberExpression)expression.Body).Member.Name; // "DoStuff"
}
public void SomewhereElse()
{
…
Dave Cameron
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120
votes
2 answers
Func() vs Func.Invoke()
I'm curious about the differences between calling a Func directly vs. using Invoke() on it. Is there a difference? Is the first syntactical sugar and calls Invoke() underneath anyway?
public T DoWork(Func method)
{
return…
tris
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110
votes
12 answers
How to make a random color with Swift
How I can make a random color function using Swift?
import UIKit
class ViewController: UIViewController {
var randomNumber = arc4random_uniform(20)
var randomColor = arc4random()
//Color Background randomly
func colorBackground()…
Giovanie Rodz
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91
votes
4 answers
Explanation of Func
I was wondering if someone could explain what Func is and how it is used with some clear examples.
zSynopsis
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votes
7 answers
Go map of functions
I have Go program that has a function defined. I also have a map that should have a key for each function. How can I do that?
I have tried this, but this doesn't work.
func a(param string) {
}
m := map[string] func {
'a_func': a,
}
for key,…
Conceited Code
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votes
8 answers
Creating delegates manually vs using Action/Func delegates
Today I was thinking about declaring this:
private delegate double ChangeListAction(string param1, int number);
but why not use this:
private Func ChangeListAction;
or if ChangeListAction would have no return value I could…
Elisabeth
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76
votes
2 answers
Func delegate with ref variable
public object MethodName(ref float y)
{
// elided
}
How do I define a Func delegate for this method?
chugh97
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9 answers
How do you use Func<> and Action<> when designing applications?
All the examples I can find about Func<> and Action<> are simple as in the one below where you see how they technically work but I would like to see them used in examples where they solve problems that previously could not be solved or could be…
Edward Tanguay
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6 answers
Can you get a Func (or similar) from a MethodInfo object?
I realize that, generally speaking, there are performance implications of using reflection. (I myself am not a fan of reflection at all, actually; this is a purely academic question.)
Suppose there exists some class that looks like this:
public…
Dan Tao
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58
votes
5 answers
Array and slice data types
I found myself confused with the array and slice data types.
From Go docs, arrays are described as follows:
There are major differences between the ways arrays work in Go and C. In Go,
Arrays are values. Assigning one array to another copies all…
duganets
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