Dart assign a function/method to variable after declaration

Question

I want to assign a function, with parameters, to an already declared variable, So I be able to execute it later.

Something like that:

void main() {
  Function p;
  p = print('1'); // should not execute;
  p;
}

How do I do that? Is it possible?

Md. Yeasin Sheikh · Accepted Answer · 2021-12-23 13:38:19Z

7

You can do it like

void main() {
  late Function p;
  p = () {
    print('1');
  };
  p(); // it will print 1
}

answered Dec 23, 2021 at 13:38

Md. Yeasin Sheikh

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Comments

Amir Hossein Rahmanzadeh · Accepted Answer · 2021-12-23 13:37:02Z

3

For the example you have provided you can do this:

void main() {
  Function p = (){print('1');};
}

now you can call p() to execute it later.

answered Dec 23, 2021 at 13:37

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Thanks Amir, but in my case I have to assign my function after the deceleration

@genericUser You’re welcome, nothing changes actually, you can do it this way: void main() { late Function p; p = () { print('1'); }; p(); }

Maurice Raguse · Accepted Answer · 2021-12-23 13:36:40Z

2

 void Function(Object? object) p;
 p = print; 
 p.call('1');

answered Dec 23, 2021 at 13:36

Maurice Raguse

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Hey @Raegtime thanks for replying, I have edited my question. I need to assign my the function after declaring the variable.

void Function(Object? object) p; p = ()=>print('1'); p.call();