UpDownBase.ReadOnly Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
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
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.