I have just installed C# for the first time, and at first glance it appears to be very similar to VB6. I decided to start off by trying to make a 'Hello, World!' UI Edition.
I started in the Form Designer and made a button named "Click Me!" proceeded to double-click it and typed in
MessageBox("Hello, World!");
I received the following error:
MessageBox is a 'type' but used as a 'variable'
Fair enough, it seems in C# MessageBox is an Object. I tried the following
MessageBox a = new MessageBox("Hello, World!");
I received the following error:
MessageBox does not contain a constructor that takes '1' arguments
Now I am stumped. Please help.
MessageBox.Show also returns a DialogResult, which if you put some buttons on there, means you can have it returned what the user clicked. Most of the time I write something like
if (MessageBox.Show("Do you want to continue?", "Question", MessageBoxButtons.YesNo) == MessageBoxResult.Yes) {
//some interesting behaviour here
}
which I guess is a bit unwieldy but it gets the job done.
See https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.dialogresult for additional enum options you can use here.
Code summary:
using System.Windows.Forms;
...
MessageBox.Show( "hello world" );
Also (as per this other stack post): In Visual Studio expand the project in Solution Tree, right click on References, Add Reference, Select System.Windows.Forms on Framework tab. This will get the MessageBox working in conjunction with the using System.Windows.Forms reference from above.
It is a static function on the MessageBox class, the simple way to do this is using
MessageBox.Show("my message");
in the System.Windows.Forms class. You can find more on the msdn page for this here . Among other things you can control the message box text, title, default button, and icons. Since you didn't specify, if you are trying to do this in a webpage you should look at triggering the javascript alert("my message"); or confirm("my question"); functions.
Try below code:
MessageBox.Show("Test Information Message", "Caption", MessageBoxButtons.OK, MessageBoxIcon.Information);
Also you can use a MessageBox with OKCancel options, but it requires many codes.
The if block is for OK, the else block is for Cancel. Here is the code:
if (MessageBox.Show("Are you sure you want to do this?", "Question", MessageBoxButtons.OKCancel, MessageBoxIcon.Question) == DialogResult.OK)
{
MessageBox.Show("You pressed OK!");
}
else
{
MessageBox.Show("You pressed Cancel!");
}
You can also use a MessageBox with YesNo options:
if (MessageBox.Show("Are you sure want to doing this?", "Question", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
{
MessageBox.Show("You are pressed Yes!");
}
else
{
MessageBox.Show("You are pressed No!");
}
In the System.Windows.Forms class, you can find more on the MSDN page for this here. Among other things you can control the message box text, title, default button, and icons. Since you didn't specify, if you are trying to do this in a webpage you should look at triggering the javascript alert("my message"); or confirm("my question"); functions.
This is some of the things you can put into a message box. Enjoy
MessageBox.Show("Enter the text for the message box",
"Enter the name of the message box",
(Enter the button names e.g. MessageBoxButtons.YesNo),
(Enter the icon e.g. MessageBoxIcon.Question),
(Enter the default button e.g. MessageBoxDefaultButton.Button1)
More information can be found here
I got the same error 'System.Windows.Forms.MessageBox' is a 'type' but is used like a 'variable', even if using:
MessageBox.Show("Hello, World!");
I guess my initial attempts with invalid syntax caused some kind of bug and I ended up fixing it by adding a space between "MessageBox.Show" and the brackets ():
MessageBox.Show ("Hello, World!");
Now using the original syntax without the extra space works again:
MessageBox.Show("Hello, World!");
Related
I am trying to add a confirmation messagebox in C# code and the examples I have found and I have added the below example but I keep getting error message "The name 'MessageBox' does not exist in the current context" I am pretty new to C# and need help as I need a confirmation message for the user of the page.
I have tried adding the Using system.windows.form to see if that resolves the messagebox issue but so far no luck
const string message = "Are you sure that you would like to close the form?";
const string caption = "Form Closing";
var result = MessageBox.Show(message, caption,
MessageBoxButtons.YesNo,
MessageBoxIcon.Question);
// If the no button was pressed ...
if (result == DialogResult.No)
{
// cancel the closure of the form.
e.Cancel = true;
}
Based on a compare I will perform, I will need this messagebox to prompt and ask the user if they are sure they want to continue or not and if not it is to return to the page, if so then the new code executes.
In the Solution Explorer: Right Click your Project -> Add -> Reference... -> Assemblies -> In the top right is a searchbar, enter "Forms" -> System.Windows.Forms -> OK
You are missing adding references to the System.Windows.Forms dll. Please add the references and using statement.
In my Windows application, I want to when ever user try to delete a row from datagridview then there should be a open a messagebox, asking user to confirm the deletion of that row.
For this purpose I have written this code:
DialogResult res = MessageBox.Show("Are You Sure", MessageBoxButtons.OKCancel);
and check the user user response but this line shows error.
What is wrong with this code?
Please help me.
When I write only this code
MessageBox.Show("Are You Sure");
then it is working fine, but I want to confirm the user again so I want his response.
You are almost there! If you want to specify MessageBoxButtons you need to add a title as well as a caption (or message text) in this manner:
MessageBox.Show(string, string, MessageBoxButtons);
Completed, your code should look something like this:
DialogResult res = MessageBox.Show("Are you sure?", "Title", MessageBoxButtons.OKCancel);
You are getting the error, because your debugger is expecting a string for a Title and is receiving MessageBoxButtons instead. Read this article for a detailed explanation.
According to the MessageBox API There is no method overload for Show(String, MessageBoxButtons)
I think you want
Show(String, String, MessageBoxButtons)
Use the MessageBoxResult instead:
MessageBoxResult res= MessageBox.Show("Are You Sure",MessageBoxButtons.OKCancel);
I have a WinForms application, and when it is finished running, displays a message box with just an OK button.
Is it possible to have an OPEN button on the message box too?
I found this code online:
public static DialogResult Show(string text, string caption, MessageBoxButtons buttons);
But it only gives basic commands, like Yes / No, OK / Cancel, etc. It doesn't show any open button.
I want to OPEN a text file after my program has finished running.
Any help would be greatly appreciated.
No, you can't have any other values in a message box rather than the default, the MessageBoxButtons is predefined enum and you can't add to it. The solution is either use some custom message box, check this, or implement your own MessageBoxForm and add your custom settings to it, check this.
The MessageBox.Show methods exposes serval overloads. You can use one of them as you like. To invoke a MessageBox, simply execute following line:
MessageBox.Show("Hi");
For information you can find on MSDN.
I'm having a problem with a MessageBox intended to be modal.
Here is the situation,
A user select xx from the form
MessageBox appears
User opens the embebed software keyboard (the built-in one, from the device)
User closes the keyboard
The MessageBox loses focus (how? it's supossed to be modal!) and the main form is shown in the foreground
The app blocks, as the user cannot now close the MessageBox.
Here is the code snippet for the MessageBox.
MessageBox.Show("message", "caption", MessageBoxButtons.OK, MessageBoxIcon.Asterisk,
MessageBoxDefaultButton.Button1);
Any ideas on how to solve this?
This is actually somewhat expected behavior under Windows CE (I'm not saying it's right, just expected).
When you click on the SIP button down in the corner of the desktop, your entire app loses focus and focus is passed to the Task Bar. You can see similar "wierdness" by clicking on your application's Task Bar button - the MessageBox will lose focus, even though by all rights you should just be sending focus to the app that is already running.
You can see that it's not a CF bug by changing your MessageBox call like so:
private void button1_Click(object sender, EventArgs e)
{
//MessageBox.Show("message", "caption", MessageBoxButtons.OK,
// MessageBoxIcon.Asterisk,
// MessageBoxDefaultButton.Button1);
MessageBoxCE(this.Handle, "message", "caption", 0);
}
// renamed to not collide with the Windows.Forms MessageBox class
[DllImport("coredll", EntryPoint="MessageBox")]
private static extern int MessageBoxCE(IntPtr hWnd, string lpText,
string lpCaption, int Type);
And you get the exact same behavior.
The one thing that is not expected is that the parent Form is coming up above the MessageBox. I just tested on an ARM-based CE 5.0 device I have on my desktop and the MessageBox stays on top in both the CF and the P/Invoke versions.
Are you able to repro this behavior with a very basic app (i.e. just one form, one button)? If so then it sounds like a platform issue. One thing to remember about using CE is that since the OEM has a lot of control over how the OS is actually implemented, you can never rule out a platform bug for behaviors.
You need to include a reference to the parent form when calling the MessageBox.Show (the IWin32Window parameter, usually just pass in "this"). I believe this is the overload you want to use - see below:
MessageBox.Show Method (IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton)
Here is a link to the Microsoft documentation.
Enjoy!
MessageBox.Show("Please insert Correct Username and Password.", "Login Error",
MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
this.Focus();
Its a simple solution. no need to run any JavaScript or other C# Code.
I want to show messagebox to the user, such that the user cannot refuse to confirm the message box. User should not be allowed to do anything else in the screen until he confirms the messagebox. This is a windows based c# application. The main thing is, even if i use windows message box. Some times it is hiding behind some screen. But for my case, i want message box to be on top most whenever it appears. I am using some other third party applications, which over rides my message box. I want to overcome this. How to do this...
Invoke messagebox inside the constructor of your form.
public Form1()
{
if (MessageBox.Show(this, "Confirm?", "Attention", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) == DialogResult.Yes)
{
}
else
{
}
InitializeComponent();
}
OR
Invoke another form instance using ShowDialog() method,
public Form1()
{
Form2 frm=new Form2();
frm.ShowDialog(this);
}
You might have to define a custom message box (a Form) and set its TopMost property to true.This will make it on top of ever other window, except other TopMost windows.
That's assuming you want it on top of other applications too, which I'm not sure it's what you're looking for...
The normal windows MessageBox() function should do exactly this unless I'm missing something in your question.
Always specify a owner when displaying a message box.