UpDownBase.ReadOnly Property

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

UpDownBase.cs

Gets or sets a value indicating whether the text can be changed by the use of the up or down buttons only.

public:
 property bool ReadOnly { bool get(); void set(bool value); };

public bool ReadOnly { get; set; }

member this.ReadOnly : bool with get, set

Public Property ReadOnly As Boolean

Property Value

Boolean

true if the text can be changed by the use of the up or down buttons only; otherwise, false. The default value is false.

Examples

The following code example uses the derived class NumericUpDown and sets some of its properties derived from UpDownBase. This code requires that you have a NumericUpDown control, two ComboBox controls, and three CheckBox controls created on a form. Label the ComboBox controls BorderStyle and TextAlign. Label the CheckBox controls InterceptArrowKeys, ReadOnly, and UpDownAlign. The code allows you to change the property values at run time and see how each affects the appearance and behavior of the spin box. Add the following items to the combo box labeled BorderStyle: None, Fixed3D, and FixedSingle. Add the following items to the combo box labeled TextAlign: Left, Right, and Center.

void comboBox1_SelectedIndexChanged( Object^ sender, EventArgs^ e )
{
   // Set the BorderStyle property.
   if (  !String::Compare( comboBox1->Text, "Fixed3D" ) )
   {
      numericUpDown1->BorderStyle = System::Windows::Forms::BorderStyle::Fixed3D;
   }
   else
   if (  !String::Compare( comboBox1->Text, "None" ) )
   {
      numericUpDown1->BorderStyle = System::Windows::Forms::BorderStyle::None;
   }
   else
   if (  !String::Compare( comboBox1->Text, "FixedSingle" ) )
   {
      numericUpDown1->BorderStyle = System::Windows::Forms::BorderStyle::FixedSingle;
   }
}

void comboBox2_SelectedIndexChanged( Object^ sender, EventArgs^ e )
{
   // Set the TextAlign property.    
   if (  !String::Compare( comboBox2->Text, "Right" ) )
   {
      numericUpDown1->TextAlign = HorizontalAlignment::Right;
   }
   else
   if (  !String::Compare( comboBox1->Text, "Left" ) )
   {
      numericUpDown1->TextAlign = HorizontalAlignment::Left;
   }
   else
   if (  !String::Compare( comboBox1->Text, "Center" ) )
   {
      numericUpDown1->TextAlign = HorizontalAlignment::Center;
   }
}

void checkBox1_Click( Object^ sender, EventArgs^ e )
{
   // Evaluate and toggle the ReadOnly property.
   if ( numericUpDown1->ReadOnly )
   {
      numericUpDown1->ReadOnly = false;
   }
   else
   {
      numericUpDown1->ReadOnly = true;
   }
}

void checkBox2_Click( Object^ sender, EventArgs^ e )
{
   // Evaluate and toggle the InterceptArrowKeys property.
   if ( numericUpDown1->InterceptArrowKeys )
   {
      numericUpDown1->InterceptArrowKeys = false;
   }
   else
   {
      numericUpDown1->InterceptArrowKeys = true;
   }
}

void checkBox3_Click( Object^ sender, EventArgs^ e )
{
   // Evaluate and toggle the UpDownAlign property.
   if ( numericUpDown1->UpDownAlign == LeftRightAlignment::Left )
   {
      numericUpDown1->UpDownAlign = LeftRightAlignment::Right;
   }
   else
   {
      numericUpDown1->UpDownAlign = LeftRightAlignment::Left;
   }
}

private void comboBox1_SelectedIndexChanged(Object sender, 
                                             EventArgs e)
 {
      // Set the BorderStyle property.
     switch(comboBox1.Text)
     {
         case "Fixed3D":
             numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
             break;
         case "None":
             numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.None;
             break;
         case "FixedSingle":
             numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
             break;
     }
 }
 
 private void comboBox2_SelectedIndexChanged(Object sender, 
                                             EventArgs e)
 {
      // Set the TextAlign property.    
     switch (comboBox2.Text)
     {
         case "Right":
             numericUpDown1.TextAlign = HorizontalAlignment.Right;
             break;
         case "Left":
             numericUpDown1.TextAlign = HorizontalAlignment.Left;
             break;
         case "Center":
             numericUpDown1.TextAlign = HorizontalAlignment.Center;
             break;
     }
 }
 
 private void checkBox1_Click(Object sender, 
                              EventArgs e)
 {
      // Evaluate and toggle the ReadOnly property.
     if (numericUpDown1.ReadOnly)
     {
         numericUpDown1.ReadOnly = false;
     }
     else
     {
         numericUpDown1.ReadOnly = true;
     }
 }
 
 private void checkBox2_Click(Object sender, 
                              EventArgs e)
 {
      // Evaluate and toggle the InterceptArrowKeys property.
     if (numericUpDown1.InterceptArrowKeys)
     {  
         numericUpDown1.InterceptArrowKeys = false;
     }
     else
     {
         numericUpDown1.InterceptArrowKeys = true;
     }
 }
 
 private void checkBox3_Click(Object sender, 
                              EventArgs e)
 {
      // Evaluate and toggle the UpDownAlign property.
     if (numericUpDown1.UpDownAlign == LeftRightAlignment.Left)
     {
         numericUpDown1.UpDownAlign = LeftRightAlignment.Right;
     }
     else
     {
         numericUpDown1.UpDownAlign = LeftRightAlignment.Left;
     }
 }

Private Sub comboBox1_SelectedIndexChanged(sender As Object, e As EventArgs)
    ' Set the BorderStyle property.
    Select Case comboBox1.Text
        Case "Fixed3D"
            numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
        Case "None"
            numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.None
        Case "FixedSingle"
            numericUpDown1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle
    End Select
End Sub    

Private Sub comboBox2_SelectedIndexChanged(sender As Object, e As EventArgs)
    ' Set the TextAlign property.    
    Select Case comboBox2.Text
        Case "Right"
            numericUpDown1.TextAlign = HorizontalAlignment.Right
        Case "Left"
            numericUpDown1.TextAlign = HorizontalAlignment.Left
        Case "Center"
            numericUpDown1.TextAlign = HorizontalAlignment.Center
    End Select
End Sub    

Private Sub checkBox1_Click(sender As Object, e As EventArgs)
    ' Evaluate and toggle the ReadOnly property.
    If numericUpDown1.ReadOnly Then
        numericUpDown1.ReadOnly = False
    Else
        numericUpDown1.ReadOnly = True
    End If
End Sub    

Private Sub checkBox2_Click(sender As Object, e As EventArgs)
    ' Evaluate and toggle the InterceptArrowKeys property.
    If numericUpDown1.InterceptArrowKeys Then
        numericUpDown1.InterceptArrowKeys = False
    Else
        numericUpDown1.InterceptArrowKeys = True
    End If
End Sub    

Private Sub checkBox3_Click(sender As Object, e As EventArgs)
    ' Evaluate and toggle the UpDownAlign property.
    If numericUpDown1.UpDownAlign = LeftRightAlignment.Left Then
        numericUpDown1.UpDownAlign = LeftRightAlignment.Right
    Else
        numericUpDown1.UpDownAlign = LeftRightAlignment.Left
    End If
End Sub

Remarks

By setting the ReadOnly property to true, you will eliminate the need for much validation of the Text property. The user will be restricted to the use of the up and down buttons to change the Text values. It will only allow them to select values you specify.

Note

In the derived class DomainUpDown, the behavior described is slightly different. When ReadOnly is set to true and a key is pressed, the control selects the first item in the collection where the first character matches the key pressed.

See also

• Text