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KeyEventArgs.KeyValue Property

.NET Framework 4

Gets the keyboard value for a KeyDown or KeyUp event.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)
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public int KeyValue { get; }

Property Value

Type: System.Int32
The integer representation of the KeyCode property.

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the Control.KeyDown event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing MessageBox.Show with Console.WriteLine or appending the message to a multiline TextBox.

To run the example code, paste it into a project that contains an instance of a type that inherits from Control, such as a Button or ComboBox. Then name the instance Control1 and ensure that the event handler is associated with the Control.KeyDown event.

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private void Control1_KeyDown(Object sender, KeyEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Alt", e.Alt );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Control", e.Control );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Handled", e.Handled );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyCode", e.KeyCode );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyValue", e.KeyValue );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "KeyData", e.KeyData );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Modifiers", e.Modifiers );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Shift", e.Shift );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "SuppressKeyPress", e.SuppressKeyPress );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "KeyDown Event" );
}

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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this code accept a-z A-Z 0-9 space - and backspace
private void tbLayoutDescription_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Back || e.KeyCode == Keys.Space)
            {
                return;
            }
            if (e.KeyValue > 90)
            {
                e.SuppressKeyPress = true;
                return;
            }
            if (e.Shift)
            {
                e.SuppressKeyPress = true;
                return;
            }
            if (Convert.ToChar(e.KeyValue) >= 'A' && Convert.ToChar(e.KeyValue) <= 'Z' ||
                Convert.ToChar(e.KeyValue) >= 'a' && Convert.ToChar(e.KeyValue) <= 'z' ||
                Convert.ToChar(e.KeyValue) >= '0' && Convert.ToChar(e.KeyValue) <= '9' ||
                Convert.ToChar(e.KeyValue) == '-')
            {
                return;
            }
            e.SuppressKeyPress = true;
        }
History
Convert.ToChar not 100 percent...
The Convert.ToChar tip is good, but it doesn't handle all characters, it's treating the keycode as an ascii value.  The problem is that things like NumPad9 don't return "9" using this method, they return "i" (because the KeyCode of NumPad9 is 105, in ascii that's "i").

The way I see it is you must either map all the possible keyboard values to their characters, perform some "semi automated processing" (like get everything past "NumPad" and hope they don't select the ~ Tilde) or better yet, use the KeyPress event.
History
Classic Poor Example
I can't stand examples like those presented here. The only thing this sample code demonstrates is how to use Console.WriteLine. It does absolutely nothing to show a real-world use of the KeyValue property. For instance, I came to this page researching how KeyValue corresponds to or could be converted into a char representation (matching what KeyPress's KeyChar returns). Kudos, MSDN

Instead of walking away with anything remotely close to something helpful, instead I can walk away proudly knowing how to output variable values!
History
I know
Use: Convert.ToChar(e.KeyValue)

This will convert numbers and letters

Also a POOR editor that puts dollar-sign zeros everywhere.
History