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.NET and JavaScript UI Controls
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IsItemInList() Method

Determines if the text in the edit portion of the combo exists in the list.
Syntax
'Declaration
 
Public Overloads Function IsItemInList() As Boolean
public bool IsItemInList()

Return Value

A boolean indicating whether the text in the edit portion of the combo is a value in the control's list.
Remarks

This method searches a column in the list (determined by the UltraDropDownBase.DisplayMemberResolved property) to determine if the text current in the edit portion of the cbombo is on the list.

Example
A LimitToList property, an ItemNotInList event, and overloaded IsItemInList methods provide convenient and flexible validation strategies for the UltraCombo.

For an overview of how to handle events in Visual Basic or Visual C#, see Event Handlers in Visual Basic and Visual C#. For specific information and code examples illustrating how to consume events in your application, see Consuming Events in the .NET Framework Developer's Guide.

' LimitToList property
Private Sub Form1_Load(sender As Object, e As System.EventArgs)

   ' The LimitToList propertyspecifies whether the UltraCombo will retain focus upon
   ' validation whenever the entered value is not a value in the control's ValueList.
   Me.ultraCombo1.LimitToList = True

End Sub 'Form1_Load


' ItemNotInList event
Private Sub ultraCombo1_ItemNotInList(sender As Object, e As Infragistics.Win.UltraWinEditors.ValidationErrorEventArgs)

   ' The ItemNotInList event is fired before the Validating event of the UltraCombo whenever the
   ' text value entered into the editor portion of the control is not a value in the control’s
   ' ValueList.  The event passes a ValidationErrorEventArgs object that contains InvalidText
   ' and LastValidValue properties as well as properties for specifying that the UltraCombo
   ' should retain focus or beep to provide an auditory cue.
   ' Specifies whether the control will retain focus. Overrides the UltraCombo's LimitToList property
   ' if RetainFocus is set to false.
   e.RetainFocus = True
   
   ' Provide an auditory cue that the enetered text is invalid.  If a message box is used this will be
   ' unnecesary since the message box will provide a beep.
   e.Beep = True
   
   ' Display a message box indicating that the entered text is invalid.
   MessageBox.Show(e.InvalidText + " is not a valid value.", "Invalid Entry")
   
   ' Restore a previously valid value if one was entered, otherwise set a valid default value.
   If Not (e.LastValidValue Is Nothing) Then
      Me.ultraCombo1.Value = e.LastValidValue
   Else
      Me.ultraCombo1.SelectedRow = Me.ultraCombo1.Rows(0)
   End If

End Sub 'ultraCombo1_ItemNotInList

 
' IsItemInList overloaded methods
Private Sub button1_Click(sender As Object, e As System.EventArgs)

   ' The IsItemInList overloaded methods return a boolean indicating whether the value of the UltraCombo's
   ' Text property, or a specified string, is a value in the control's ValueList.  This provides
   ' a convenient way to perform validation in code.

   ' If the current value of the UltraCombo's Text property is not a value in the control's ValueList
   ' assign a valid text value.
   Dim currentTextIsValid As Boolean = Me.ultraCombo1.IsItemInList()
   If Not currentTextIsValid Then
      Me.ultraCombo1.Text = "Some valid text value"
   End If 

   ' If the specified string is not a value in the UltraCombo's ValueList assign a valid text value.
   Dim someText As String = "Some Text"
   Dim itemIsInList As Boolean = Me.ultraCombo1.IsItemInList(someText)
   
   If itemIsInList Then
      Me.ultraCombo1.Text = someText
   Else
      System.Diagnostics.Debug.WriteLine((someText + " is not in the list"))
   End If

End Sub 'button1_Click
// LimitToList property
private void Form1_Load(object sender, System.EventArgs e)
     {
         // The LimitToList propertyspecifies whether the UltraCombo will retain focus upon
         // validation whenever the entered value is not a value in the control's ValueList.
         this.ultraCombo1.LimitToList = true;
     }

// ItemNotInList event
     private void ultraCombo1_ItemNotInList(object sender, Infragistics.Win.UltraWinEditors.ValidationErrorEventArgs e)
     {
         // The ItemNotInList event is fired before the Validating event of the UltraCombo whenever the
         // text value entered into the editor portion of the control is not a value in the control’s
         // ValueList.  The event passes a ValidationErrorEventArgs object that contains InvalidText
         // and LastValidValue properties as well as properties for specifying that the UltraCombo
         // should retain focus or beep to provide an auditory cue.

         // Specifies whether the control will retain focus. Overrides the UltraCombo's LimitToList property
         // if RetainFocus is set to false.
         e.RetainFocus = true;

         // Provide an auditory cue that the enetered text is invalid.  If a message box is used this will be
         // unnecesary since the message box will provide a beep.
         e.Beep = true;

         // Display a message box indicating that the entered text is invalid.
         MessageBox.Show( e.InvalidText + " is not a valid value.", "Invalid Entry" );

         // Restore a previously valid value if one was entered, otherwise set a valid default value.
         if ( e.LastValidValue != null )
             this.ultraCombo1.Value = e.LastValidValue;
         else
             this.ultraCombo1.SelectedRow = this.ultraCombo1.Rows[0];
     }

// IsItemInList overloaded methods
     private void button1_Click(object sender, System.EventArgs e)
     {
         // The IsItemInList overloaded methods return a boolean indicating whether the value of the UltraCombo's
         // Text property, or a specified string, is a value in the control's ValueList.  This provides
         // a convenient way to perform validation in code.

         // If the current value of the UltraCombo's Text property is not a value in the control's ValueList
         // assign a valid text value.
         bool currentTextIsValid = this.ultraCombo1.IsItemInList();
         if ( !currentTextIsValid )
             this.ultraCombo1.Text = "Some valid text value";

         // If the specified string is not a value in the UltraCombo's ValueList assign a valid text value.
         string someText = "Some Text";
         bool itemIsInList = this.ultraCombo1.IsItemInList( someText );

         if( itemIsInList )
             this.ultraCombo1.Text = someText;
         else
             System.Diagnostics.Debug.WriteLine( someText + " is not in the list" );
     }
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

See Also