139

I am using System.Windows.Forms but strangely enough don't have the ability to create them.

How can I get something like a javascript prompt dialog, without javascript?

MessageBox is nice, but there is no way for the user to enter an input.

I want the user to enter any text input possible.

user420667
  • 6,552
  • 15
  • 51
  • 83
  • Can you post a code example of what you're trying to do? – Andrew Cooper Mar 24 '11 at 23:55
  • What kind of input are you looking for, give little more details. [CommonDialog](http://msdn.microsoft.com/en-us/library/system.windows.forms.commondialog.aspx) look at the classes inheriting it do any of them look right for you? – Sanjeevakumar Hiremath Mar 24 '11 at 23:55
  • 26
    It's funny how three people ask the OP to give more details and code samples but it's pretty clear what he means by *"like a javascript prompt dialog"*. – Camilo Martin Feb 05 '13 at 04:53
  • 2
    Here are two examples, one basic and another with input validation: 1. basic - http://www.csharp-examples.net/inputbox/ 2. validation - http://www.csharp-examples.net/inputbox-class/ – CodeMonkey Apr 11 '13 at 13:29

11 Answers11

323

You need to create your own Prompt dialog. You could perhaps create a class for this.

public static class Prompt
{
    public static string ShowDialog(string text, string caption)
    {
        Form prompt = new Form()
        {
            Width = 500,
            Height = 150,
            FormBorderStyle = FormBorderStyle.FixedDialog,
            Text = caption,
            StartPosition = FormStartPosition.CenterScreen
        };
        Label textLabel = new Label() { Left = 50, Top=20, Text=text };
        TextBox textBox = new TextBox() { Left = 50, Top=50, Width=400 };
        Button confirmation = new Button() { Text = "Ok", Left=350, Width=100, Top=70, DialogResult = DialogResult.OK };
        confirmation.Click += (sender, e) => { prompt.Close(); };
        prompt.Controls.Add(textBox);
        prompt.Controls.Add(confirmation);
        prompt.Controls.Add(textLabel);
        prompt.AcceptButton = confirmation;

        return prompt.ShowDialog() == DialogResult.OK ? textBox.Text : "";
    }
}

And calling it:

string promptValue = Prompt.ShowDialog("Test", "123");

Update:

Added default button (enter key) and initial focus based on comments and another question.

Community
  • 1
  • 1
Bas
  • 26,772
  • 8
  • 53
  • 86
  • 2
    How would one extend this to A) have a cancel button and B) validate the text in the textfield in some way before returning? – ewok Jun 26 '12 at 16:08
  • @ewok Just create a form, the Forms Designer will help you lay it out the way you want to. – Camilo Martin Feb 05 '13 at 03:32
  • Nice and quick solution! I just added prompt.Height = 150; before the ShowDialog to get all controls on the window. – werner Feb 22 '13 at 09:18
  • This doesn't address the user's question. This creates a Form object, and the user explicitly stated that they cannot do that. – Sean Worle May 07 '14 at 19:12
  • 1
    @SeanWorle I don't see where that is mentioned. – Bas May 08 '14 at 09:17
  • Right in the beginning of the question: "I am using System.Windows.Forms but strangely enough don't have the ability to create them." He does not have the ability to create a Form object, based on that question. – Sean Worle May 09 '14 at 13:16
  • "them" refers to the prompt – Bas May 09 '14 at 14:00
  • I added this (pet peeve alert): prompt.StartPosition = FormStartPosition.CenterScreen; – B. Clay Shannon-B. Crow Raven May 23 '14 at 22:08
  • @BasBrekelmans: Thanks; based on this: http://stackoverflow.com/questions/23839151/why-does-calling-focus-not-set-focus-in-this-instance/23839286, I also added ", TabIndex = 0, TabStop = true" to the textbox so it would get the focus (and ", TabIndex = 1, TabStop = true" to the button). The last thing I want is for Enter to close the form / have the Okay button be the default action. – B. Clay Shannon-B. Crow Raven May 23 '14 at 22:53
  • 1
    Which I accomplished by adding this: prompt.AcceptButton = confirmation; – B. Clay Shannon-B. Crow Raven May 23 '14 at 22:54
  • Added `prompt.FormBorderStyle = FormBorderStyle.FixedDialog` to disable resizing. – arao6 Nov 10 '14 at 20:59
  • 1
    Added code to handle user cancelling the prompt with the close button and the returning an empty string – Matthew Lock Jun 14 '15 at 02:28
  • Minor nitpick, should be commas separating property values in the Form initializer, not semi-colons. – EricRRichards Jan 14 '16 at 15:13
  • I was able to use this in an InstallShield project for dynamic input for an "Advanced" setting. Excellent answer. – Caleb Adams Oct 28 '16 at 15:59
  • Add `if (text == null) text = ""; if (caption == null) caption = "";` to allow blank for either text or caption – TheAtomicOption Sep 05 '17 at 22:21
  • Thanks for this! Here's my slight update adding an optional "defaultInputText" parameter to allow specifying the default input text in the prompt: https://gist.github.com/41adb68ce1b6c5adf56ba8b967c7ff16 – Christopher Dec 26 '18 at 14:34
  • This is good but I tried it out and found it will not accept any symbols, such as a colon. When I type in a colon in the string sent to the "text" variable, all characters after the colon are cut off. Gideon's example does not have this bug. – SendETHToThisAddress Dec 28 '18 at 08:05
  • So many people used this prompt that Github Copilot is using it and on demand adding this code exactly like seen here. – John Nov 09 '22 at 05:19
  • would be nice to have "AutoSize = true" for the Label. – Victor Lee Jan 05 '23 at 21:53
62

Add reference to Microsoft.VisualBasic and use this into your C# code:

string input = Microsoft.VisualBasic.Interaction.InputBox("Prompt", 
                       "Title", 
                       "Default", 
                       0, 
                       0);

To add the refernce: right-click on the References in your Project Explorer window then on Add Reference, and check VisualBasic from that list.

StayOnTarget
  • 11,743
  • 10
  • 52
  • 81
KurvaBG
  • 629
  • 5
  • 2
13

There is no such thing natively in Windows Forms.

You have to create your own form for that or:

use the Microsoft.VisualBasic reference.

Inputbox is legacy code brought into .Net for VB6 compatibility - so i advise to not do this.

t0mm13b
  • 34,087
  • 8
  • 78
  • 110
Marino Šimić
  • 7,318
  • 1
  • 31
  • 61
  • 3
    This is true for the `Microsoft.VisualBasic.Compatibility` namespace. `Microsoft.VisualBasic` is more a set of helper libraries on top of .Net and isn't really VB specific at all. – Jim Wooley Sep 26 '19 at 14:51
  • -1 because of the inacurrate statement about the VB reference. No reason to scare people away from using this very useful built-in feature. – StayOnTarget Apr 24 '20 at 20:11
9

The answer of Bas can get you in memorytrouble theoretically, since ShowDialog won't be disposed. I think this is a more proper way. Also mention the textLabel being readable with longer text.

public class Prompt : IDisposable
{
    private Form prompt { get; set; }
    public string Result { get; }

    public Prompt(string text, string caption)
    {
        Result = ShowDialog(text, caption);
    }
    //use a using statement
    private string ShowDialog(string text, string caption)
    {
        prompt = new Form()
        {
            Width = 500,
            Height = 150,
            FormBorderStyle = FormBorderStyle.FixedDialog,
            Text = caption,
            StartPosition = FormStartPosition.CenterScreen,
            TopMost = true
        };
        Label textLabel = new Label() { Left = 50, Top = 20, Text = text, Dock = DockStyle.Top, TextAlign = ContentAlignment.MiddleCenter };
        TextBox textBox = new TextBox() { Left = 50, Top = 50, Width = 400 };
        Button confirmation = new Button() { Text = "Ok", Left = 350, Width = 100, Top = 70, DialogResult = DialogResult.OK };
        confirmation.Click += (sender, e) => { prompt.Close(); };
        prompt.Controls.Add(textBox);
        prompt.Controls.Add(confirmation);
        prompt.Controls.Add(textLabel);
        prompt.AcceptButton = confirmation;

        return prompt.ShowDialog() == DialogResult.OK ? textBox.Text : "";
    }

    public void Dispose()
    {
        //See Marcus comment
        if (prompt != null) { 
            prompt.Dispose(); 
        }
    }
}

Implementation:

using(Prompt prompt = new Prompt("text", "caption")){
    string result = prompt.Result;
}
Gideon Mulder
  • 344
  • 3
  • 6
  • 2
    Good use of memory management. But, this fails when adding a cancel button because the `prompt` is null at that point. A simple fix to allow cancelling of the prompt is to replace `prompt.Dispose();` inside of `public void Dispose()` with `if (prompt != null) { prompt.Dispose(); }` – Marcus Parsons Jun 17 '19 at 20:21
7

It's generally not a real good idea to import the VisualBasic libraries into C# programs (not because they won't work, but just for compatibility, style, and ability to upgrade), but you can call Microsoft.VisualBasic.Interaction.InputBox() to display the kind of box you're looking for.

If you can create a Windows.Forms object, that would be best, but you say you cannot do that.

Sean Worle
  • 861
  • 1
  • 7
  • 19
  • 29
    Why is this not a good idea? What are the possible "compatibility" and "ability to upgrade" problems? I'll agree that "stylistically" speaking, most C# programmers would prefer not to use classes from a namespace called `VisualBasic`, but that's only in their head. There's no reality to that feeling. It would just as well be called the `Microsoft.MakeMyLifeEasierWithAlreadyImplementedMethods` namespace. – Cody Gray - on strike May 19 '11 at 03:54
  • 3
    In general, the Microsoft.VisualBasic package is meant to simplify upgrading code from VB 6 only. Microsoft keeps threatening to permanently sunset VB (though this will probably never actually happen), so future support for this namespace is not guaranteed. Additionally, one of the advantages to .Net is supposed to be portability - the same code will run on any platform that has the .Net framework installed. Microsoft.VisualBasic, however, is not guaranteed to be available on any other platform (including, for what it's worth, .Net mobile, where it is not available at all). – Sean Worle Jun 07 '11 at 15:40
  • 23
    **Incorrect.** That's the `Microsoft.VisualBasic.Compatibility` sub-namespace, not the entire thing. Lots of "core" functionality is included in the `Microsoft.VisualBasic` namespace; it isn't going anywhere. Microsoft has threatened to "sunset" VB 6, not VB.NET. They've promised *repeatedly* that it's not going anywhere. Some people still don't seem to have figured out the difference... – Cody Gray - on strike Jun 07 '11 at 15:41
  • 1
    This answer got some points recently, and so caught my eye. I remember this conversation with @CodyGray - Maybe I'm being petty, but I wanted to point out that in the years since this discussion about how the Microsoft.VisualBasic namespace "isn't going anywhere"... in .Net Core and Standard, Microsoft.VisualBasic.Interaction.InputBox() no longer exists. – Sean Worle Oct 20 '20 at 23:06
  • It exists on Core 1,2,3.1 and probably does in .net standard. Doesn't mean you should use it, however you can. I don't think winForms is in Core into 5.0 – Nick Turner Apr 26 '23 at 20:34
4

Other way of doing this: Assuming that you have a TextBox input type, Create a Form, and have the textbox value as a public property.

public partial class TextPrompt : Form
{
    public string Value
    {
        get { return tbText.Text.Trim(); }
    }

    public TextPrompt(string promptInstructions)
    {
        InitializeComponent();

        lblPromptText.Text = promptInstructions;
    }

    private void BtnSubmitText_Click(object sender, EventArgs e)
    {
        Close();
    }

    private void TextPrompt_Load(object sender, EventArgs e)
    {
        CenterToParent();
    }
}

In the main form, this will be the code:

var t = new TextPrompt(this, "Type the name of the settings file:");
t.ShowDialog()

;

This way, the code looks cleaner:

  1. If validation logic is added.
  2. If various other input types are added.
user2347528
  • 580
  • 1
  • 8
  • 22
4

Based on the work of Bas Brekelmans above, I have also created two derivations -> "input" dialogs that allow you to receive from the user both a text value and a boolean (TextBox and CheckBox):

public static class PromptForTextAndBoolean
{
    public static string ShowDialog(string caption, string text, string boolStr)
    {
        Form prompt = new Form();
        prompt.Width = 280;
        prompt.Height = 160;
        prompt.Text = caption;
        Label textLabel = new Label() { Left = 16, Top = 20, Width = 240, Text = text };
        TextBox textBox = new TextBox() { Left = 16, Top = 40, Width = 240, TabIndex = 0, TabStop = true };
        CheckBox ckbx = new CheckBox() { Left = 16, Top = 60, Width = 240, Text = boolStr };
        Button confirmation = new Button() { Text = "Okay!", Left = 16, Width = 80, Top = 88, TabIndex = 1, TabStop = true };
        confirmation.Click += (sender, e) => { prompt.Close(); };
        prompt.Controls.Add(textLabel);
        prompt.Controls.Add(textBox);
        prompt.Controls.Add(ckbx);
        prompt.Controls.Add(confirmation);
        prompt.AcceptButton = confirmation;
        prompt.StartPosition = FormStartPosition.CenterScreen;
        prompt.ShowDialog();
        return string.Format("{0};{1}", textBox.Text, ckbx.Checked.ToString());
    }
}

...and text along with a selection of one of multiple options (TextBox and ComboBox):

public static class PromptForTextAndSelection
{
    public static string ShowDialog(string caption, string text, string selStr)
    {
        Form prompt = new Form();
        prompt.Width = 280;
        prompt.Height = 160;
        prompt.Text = caption;
        Label textLabel = new Label() { Left = 16, Top = 20, Width = 240, Text = text };
        TextBox textBox = new TextBox() { Left = 16, Top = 40, Width = 240, TabIndex = 0, TabStop = true };
        Label selLabel = new Label() { Left = 16, Top = 66, Width = 88, Text = selStr };
        ComboBox cmbx = new ComboBox() { Left = 112, Top = 64, Width = 144 };
        cmbx.Items.Add("Dark Grey");
        cmbx.Items.Add("Orange");
        cmbx.Items.Add("None");
        Button confirmation = new Button() { Text = "In Ordnung!", Left = 16, Width = 80, Top = 88, TabIndex = 1, TabStop = true };
        confirmation.Click += (sender, e) => { prompt.Close(); };
        prompt.Controls.Add(textLabel);
        prompt.Controls.Add(textBox);
        prompt.Controls.Add(selLabel);
        prompt.Controls.Add(cmbx);
        prompt.Controls.Add(confirmation);
        prompt.AcceptButton = confirmation;
        prompt.StartPosition = FormStartPosition.CenterScreen;
        prompt.ShowDialog();
        return string.Format("{0};{1}", textBox.Text, cmbx.SelectedItem.ToString());
    }
}

Both require the same usings:

using System;
using System.Windows.Forms;

Call them like so:

Call them like so:

PromptForTextAndBoolean.ShowDialog("Jazz", "What text should accompany the checkbox?", "Allow Scat Singing"); 

PromptForTextAndSelection.ShowDialog("Rock", "What should the name of the band be?", "Beret color to wear");
B. Clay Shannon-B. Crow Raven
  • 8,547
  • 144
  • 472
  • 862
2

Bas Brekelmans's answer is very elegant in its simplicity. But, I found that for an actual application a little more is needed such as:

  • Grow form appropriately when message text is too long.
  • Doesn't automatically popup in middle of screen.
  • Doesn't provide any validation of user input.

The class here handles these limitations: http://www.codeproject.com/Articles/31315/Getting-User-Input-With-Dialogs-Part-1

I just downloaded source and copied InputBox.cs into my project.

Surprised there isn't something even better though... My only real complaint is it caption text doesn't support newlines in it since it uses a label control.

blak3r
  • 16,066
  • 16
  • 78
  • 98
2

Unfortunately C# still doesn't offer this capability in the built in libs. The best solution at present is to create a custom class with a method that pops up a small form. If you're working in Visual Studio you can do this by clicking on Project >Add class

Add Class

Visual C# items >code >class Add Class 2

Name the class PopUpBox (you can rename it later if you like) and paste in the following code:

using System.Drawing;
using System.Windows.Forms;

namespace yourNameSpaceHere
{
    public class PopUpBox
    {
        private static Form prompt { get; set; }

        public static string GetUserInput(string instructions, string caption)
        {
            string sUserInput = "";
            prompt = new Form() //create a new form at run time
            {
                Width = 500, Height = 150, FormBorderStyle = FormBorderStyle.FixedDialog, Text = caption,
                StartPosition = FormStartPosition.CenterScreen, TopMost = true
            };
            //create a label for the form which will have instructions for user input
            Label lblTitle = new Label() { Left = 50, Top = 20, Text = instructions, Dock = DockStyle.Top, TextAlign = ContentAlignment.TopCenter };
            TextBox txtTextInput = new TextBox() { Left = 50, Top = 50, Width = 400 };

            ////////////////////////////OK button
            Button btnOK = new Button() { Text = "OK", Left = 250, Width = 100, Top = 70, DialogResult = DialogResult.OK };
            btnOK.Click += (sender, e) => 
            {
                sUserInput = txtTextInput.Text;
                prompt.Close();
            };
            prompt.Controls.Add(txtTextInput);
            prompt.Controls.Add(btnOK);
            prompt.Controls.Add(lblTitle);
            prompt.AcceptButton = btnOK;
            ///////////////////////////////////////

            //////////////////////////Cancel button
            Button btnCancel = new Button() { Text = "Cancel", Left = 350, Width = 100, Top = 70, DialogResult = DialogResult.Cancel };
            btnCancel.Click += (sender, e) => 
            {
                sUserInput = "cancel";
                prompt.Close();
            };
            prompt.Controls.Add(btnCancel);
            prompt.CancelButton = btnCancel;
            ///////////////////////////////////////

            prompt.ShowDialog();
            return sUserInput;
        }

        public void Dispose()
        {prompt.Dispose();}
    }
}

You will need to change the namespace to whatever you're using. The method returns a string, so here's an example of how to implement it in your calling method:

bool boolTryAgain = false;

do
{
    string sTextFromUser = PopUpBox.GetUserInput("Enter your text below:", "Dialog box title");
    if (sTextFromUser == "")
    {
        DialogResult dialogResult = MessageBox.Show("You did not enter anything. Try again?", "Error", MessageBoxButtons.YesNo);
        if (dialogResult == DialogResult.Yes)
        {
            boolTryAgain = true; //will reopen the dialog for user to input text again
        }
        else if (dialogResult == DialogResult.No)
        {
            //exit/cancel
            MessageBox.Show("operation cancelled");
            boolTryAgain = false;
        }//end if
    }
    else
    {
        if (sTextFromUser == "cancel")
        {
            MessageBox.Show("operation cancelled");
        }
        else
        {
            MessageBox.Show("Here is the text you entered: '" + sTextFromUser + "'");
            //do something here with the user input
        }

    }
} while (boolTryAgain == true);

This method checks the returned string for a text value, empty string, or "cancel" (the getUserInput method returns "cancel" if the cancel button is clicked) and acts accordingly. If the user didn't enter anything and clicked OK it will tell the user and ask them if they want to cancel or re-enter their text.

Post notes: In my own implementation I found that all of the other answers were missing 1 or more of the following:

  • A cancel button
  • The ability to contain symbols in the string sent to the method
  • How to access the method and handle the returned value.

Thus, I have posted my own solution. I hope someone finds it useful. Credit to Bas and Gideon + commenters for your contributions, you helped me to come up with a workable solution!

SendETHToThisAddress
  • 2,756
  • 7
  • 29
  • 54
1

here's my refactored version which accepts multiline/single as an option

   public string ShowDialog(string text, string caption, bool isMultiline = false, int formWidth = 300, int formHeight = 200)
        {
            var prompt = new Form
            {
                Width = formWidth,
                Height = isMultiline ? formHeight : formHeight - 70,
                FormBorderStyle = isMultiline ? FormBorderStyle.Sizable : FormBorderStyle.FixedSingle,
                Text = caption,
                StartPosition = FormStartPosition.CenterScreen,
                MaximizeBox = isMultiline
            };

            var textLabel = new Label
            {
                Left = 10,
                Padding = new Padding(0, 3, 0, 0),
                Text = text,
                Dock = DockStyle.Top
            };

            var textBox = new TextBox
            {
                Left = isMultiline ? 50 : 4,
                Top = isMultiline ? 50 : textLabel.Height + 4,
                Multiline = isMultiline,
                Dock = isMultiline ? DockStyle.Fill : DockStyle.None,
                Width = prompt.Width - 24,
                Anchor = isMultiline ? AnchorStyles.Left | AnchorStyles.Top : AnchorStyles.Left | AnchorStyles.Right
            };

            var confirmationButton = new Button
            {
                Text = @"OK",
                Cursor = Cursors.Hand,
                DialogResult = DialogResult.OK,
                Dock = DockStyle.Bottom,
            };

            confirmationButton.Click += (sender, e) =>
            {
                prompt.Close();
            };

            prompt.Controls.Add(textBox);
            prompt.Controls.Add(confirmationButton);
            prompt.Controls.Add(textLabel);

            return prompt.ShowDialog() == DialogResult.OK ? textBox.Text : string.Empty;
        }
Alper Ebicoglu
  • 8,884
  • 1
  • 49
  • 55
-1

Here's an example in VB.NET

Public Function ShowtheDialog(caption As String, text As String, selStr As String) As String
    Dim prompt As New Form()
    prompt.Width = 280
    prompt.Height = 160
    prompt.Text = caption
    Dim textLabel As New Label() With { _
         .Left = 16, _
         .Top = 20, _
         .Width = 240, _
         .Text = text _
    }
    Dim textBox As New TextBox() With { _
         .Left = 16, _
         .Top = 40, _
         .Width = 240, _
         .TabIndex = 0, _
         .TabStop = True _
    }
    Dim selLabel As New Label() With { _
         .Left = 16, _
         .Top = 66, _
         .Width = 88, _
         .Text = selStr _
    }
    Dim cmbx As New ComboBox() With { _
         .Left = 112, _
         .Top = 64, _
         .Width = 144 _
    }
    cmbx.Items.Add("Dark Grey")
    cmbx.Items.Add("Orange")
    cmbx.Items.Add("None")
    cmbx.SelectedIndex = 0
    Dim confirmation As New Button() With { _
         .Text = "In Ordnung!", _
         .Left = 16, _
         .Width = 80, _
         .Top = 88, _
         .TabIndex = 1, _
         .TabStop = True _
    }
    AddHandler confirmation.Click, Sub(sender, e) prompt.Close()
    prompt.Controls.Add(textLabel)
    prompt.Controls.Add(textBox)
    prompt.Controls.Add(selLabel)
    prompt.Controls.Add(cmbx)
    prompt.Controls.Add(confirmation)
    prompt.AcceptButton = confirmation
    prompt.StartPosition = FormStartPosition.CenterScreen
    prompt.ShowDialog()
    Return String.Format("{0};{1}", textBox.Text, cmbx.SelectedItem.ToString())
End Function
user890332
  • 1,315
  • 15
  • 15