C# :how to have message box within an event handler that freezes the application until Ok is pressed?

Question

Hi I have this in the main

  NetworkChange.NetworkAddressChanged += new NetworkAddressChangedEventHandler(AddressChangedCallback);
//The main also contains a form

and this method below it .

static void AddressChangedCallback(object sender, EventArgs e){
// would like to have a message box here that freezes the entire application
including  the form as mentioned above , untill OK is pressed"
}

What do you use? WPF, WinForms? Did you try `MessageBox.Show`? — Centro, Jun 07 '11 at 00:28

score 4 · Accepted Answer · edited May 23 '17 at 12:06

4

I'm assuming this is a WinForms application. NetworkAddressChanged event is invoked on a background thread. This is why when you display a message box from there your app stays active.

Solution 1: You need to marshal this call to your main UI thread. You can do this by using Invoke method on your main form. Define a method on the form class to show message box. Call this method using Invoke method on your main form.

Solution 2: C# / .NET messagebox is not modal

edited May 23 '17 at 12:06

Community

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answered Jun 07 '11 at 00:40

Andrew Savinykh

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hi zespri ... its a a plain console application . Is it possible to do the same as you suggested .. ? – HelloWorld_Always Jun 07 '11 at 03:32
@HelloWorld_Always: In you question you say "The main also contains a form". What do you mean by this if it's not WinForms? – Andrew Savinykh Jun 07 '11 at 03:50
@HelloWorld_Always: Consider accepting the answer if it satisfies you. – Andrew Savinykh Jun 07 '11 at 19:15

score 0 · Answer 2 · answered Jun 07 '11 at 00:43

0

It is called modal and modeless. Show is modeless, ShowDialog is modal. You can read more here.

answered Jun 07 '11 at 00:43

CharithJ

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MessageBox class produces a message box that is always modal relative to its parent. This is different from showing *forms* in modal mode. – Andrew Savinykh Jun 07 '11 at 00:47
@Zespri : ShowDialog allows to specify the parent when showing forms. – CharithJ Jun 07 '11 at 00:49

C# :how to have message box within an event handler that freezes the application until Ok is pressed?

2 Answers2