Disable MaximizeBox and MinimizeBox for MDI Child Form

Question

I can't disable the maximize and minimize box without setting ControlBox = False when the child form is maximized, anyone know the workaround for this?

I have set the mdi child form property as below:

FormBorderStyle = FixedSingle
ControlBox = True
MaximizeBox = False
MinimizeBox = False
WindowState = Maximized

I am able to fix this by doing the following:

ChildForm.WindowState = Normal;
ChildForm.MDIParent = this;
ChildForm.Show();
ChildForm.WindowState = Maximized;

what happen was, when I open 2nd child form, the minimized box enabled again....

Frogleg · Answer

OK on the properties of the menu strip select the lightening icon In the list, select ItemAdded and double click this will appear in code window private void menuStrip1_ItemAdded(object sender, ToolStripItemEventArgs e) { *** } Add this where the asterisk is and see if thats what you want string s =(e.Item.GetType().ToString()) ; if (s == "System.Windows.Forms.MdiControlStrip+ControlBoxMenuItem") { e.Item.Visible = false ; } so you should have this private void menuStrip1_ItemAdded(object sender, ToolStripItemEventArgs e) { string s =(e.Item.GetType().ToString()) ; if (s == "System.Windows.Forms.MdiControlStrip+ControlBoxMenuItem") { e.Item.Visible = false ; } }

Priyamtheone · Answer

Hi @eddom. This thread has been very helpful. By the way, could you sort out how to classify particularly which MdiControlStrip+ControlBoxMenuItem to work with? Suppose I want to make the 'Restore' button invisible. How can I do that? Regards!

Priyamtheone · Answer

Nice work around @Frogleg. However, I would like to ask you, how do you identify which MdiControlStrip+ControlBoxMenuItem to work with? Because all those three buttons return their type as 'MdiControlStrip+ControlBoxMenuItem' in strings. Suppose, I want to make particularly the 'Restore' button invisible. How do I go ahead with that? Regards!

Pankaj Gupta · Answer

Hello Eddom, I have same requiremet as you want. I have tried a lot but still not able to fullfill the requirement. Please give some suggestion that how may i do?

eddom · Answer

Frogleg, its working, now I just have to sort out which item is the one that I wanted to disable, thanks for the workaround suggestion.

eddom · Answer

Frogleg, the work around sound possible. Let me try. Thanks for the idea.

eddom · Answer

Sam Hobbs, then you should ask why Microsoft provide such property and it does not work as what it should. Setting property "MaximizeBox" = false obviously is to disable the access to the maximized box. If you read my first post carefully, the "MaximizeBox" is disabled, if I initiate the .Show() before I set the form to maximize, if I do it another way around, the maximize box would not been disabled. It sound like a bugs of .net or there is some hidden rule rather than improper usage. For me, there isn't so call beginner way of doing things in programming, sometimes, your so call beginner way, solve complex issue. I am trying to avoid to use something complex for a simple function that suppose been easily supported by the MDI form feature.

Sam Hobbs · Answer

Beginners often try to use MDI windows in the manner you are but MDI windows were not designed to be used that way. I am not sure what would be the best solution but you should explore alternatives. Perhaps a tab control would be more appropriate or a panel but I am not sure.

eddom · Answer

Child, I want to disable the red circle as shown in the image:

Frogleg · Answer

Which form is it you don't want minimized, the parent or the child ?

eddom · Answer

Not really, minimize mean do not allow user to minimize the windows; the windows must always in maximized mode. btw, I am able to disable/hide everything by setting the ControlBox = false, but again, users only do not allow to restore ("-" symbol) and minimize the windows, closing of windows is allowed. :)

Frogleg · Answer

By minimize you don't mean close do you ? private void PatientDatabaseForm_FormClosing(object sender, FormClosingEventArgs e) { e.Cancel = true; } will stop close button

eddom · Answer

Not really, the requirement happen to be all child windows shall be maximized in the mdi windows and user shall view the content in maximize mode, thus, minimizing the window shall not be allowed.

Frogleg · Answer

Is this what you want ?

eddom · Answer

Ya, FixedToolWindow suppose to behave like that, but when put it into a MDI windows, the behavior are different, I have upload the sample source code, please have a look. Thanks.

Frogleg · Answer

If you set borderstyle to FixedToolWindow there is no minimize box or maximize box - the only close box X. Do this in design view/ properties You can set Minimum size and Maximum size to the same amount so the form cannot be resized

eddom · Answer

Frogleg, thanks for the advice, but the minimized box still enabled.... this._FrmPatientDatabase = new PatientDatabaseForm(); this._FrmPatientDatabase.MdiParent = this; this._FrmPatientDatabase.MinimizeBox = false; this._FrmPatientDatabase.MaximizeBox = false; this._FrmPatientDatabase.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedToolWindow; this._FrmPatientDatabase.WindowState = FormWindowState.Maximized; this._FrmPatientDatabase.Show();

Frogleg · Answer

Set FormBorderStyle to FixedToolWindow

Sam Hobbs · Answer

I suggest not using MDI for this. MDI sounds like an easier solution for beginners but then they get hung up on problems like this that is easily solved by solutions that are designed to satisfy their requiremetns.