C maskedtextbox validatingtype
The example below shows how you could replace an existing automatically-generated "Units In Stock" column with a new custom column that supports the Masked Edit feature. Columns("Units In Stock")) ' remove the existing column Data Grid View1. Remove At(index) ' create a new custom column Dim dgv Masked Edit As New Data Grid View Masked Edit Column dgv Masked Edit.
Dim index As Integer ' find the location of the column index = Data Grid View1. Mask = "####" ' this mask will allow only numbers (max of 4) dgv Masked Edit.
The remaining overrides are to adjust to the fact that the Masked Text Box control supports multiple "validating types". Editing Control Formatted Value Get Return Me.value Is Changed. End Sub Public Read Only Property Reposition Editing Control On Value Change() As Boolean _ Implements IData Grid View Editing Control.
Public Class Data Grid View Masked Edit Cell Inherits Data Grid View Text Box Cell Dim p Column As Data Grid View Masked Edit Column Public Sub New() End Sub Public Overrides Sub Initialize Editing Control(By Val row Index As Integer, By Val _ initial Formatted Value As Object, By Val data Grid View Cell Style As Data Grid View Cell Style) My Base. To String End Get Set(By Val value As Object) If Type Of value Is [String] Then Me. To String End If End Set End Property Public Function Get Editing Control Formatted Value(By Val context As _ Data Grid View Data Error Contexts) As Object Implements _ IData Grid View Editing Control. Text End Function Public Sub Apply Cell Style To Editing Control(By Val data Grid View Cell Style As _ Data Grid View Cell Style) Implements _ IData Grid View Editing Control. Reposition Editing Control On Value Change Get Return False End Get End Property Public Property Editing Control Data Grid View() As Data Grid View Implements _ IData Grid View Editing Control.
' ' Check to see if the user input meets all of the business rules before ' we move on to another row. Data Grid View Cell Cancel Event Args) Handles _ Data Grid View1. Value The error checking discussed in the previous section may not detect "data integrity errors" (those errors where the input violates a database foreign key, unique, or primary key constraint).
' Private Sub Data Grid View1_Row Validating(By Val sender As Object, By Val e As _ System. Row Validating ' Assume that text input is complete when you attempt to navigate ' away from the row Data Grid View1. In this case we're just checking to ' see if the Unit Price is a positive number If Data Grid View1. Luckily, the Data Grid View Combo Box Column control was designed to help solve this problem.
Next, you'll need to add a Data Grid View to a form. ' create new style object Dim style As New Data Grid View Cell Style ' set the alignment to the right (for numbers) style. Middle Right ' add a wee bit of padding to the right side Dim p As New Windows. This allows you to use a "business rule" to validate the user input.
From inside the Form Designer, you should see a very small triangle at the upper right-hand corner of the Data Grid View control. For example, if the Units On Hand column can never be a negative number,you could write a validating rule that looks to see if the value is negative prior to committing the changes to that row.
The source code for the custom Data Grid View Masked Edit Column is found below.Cell Template = value End Set End Property ' ' New properties required by the Masked Text Box control ' Public Property Mask() As String Get Return p Mask End Get Set(By Val value As String) p Mask = value End Set End Property Public Property Prompt Char() As Char Get Return p Prompt Char End Get Set(By Val value As Char) p Prompt Char = value End Set End Property Public Property Validating Type() As Type Get Return p Validating Type End Get Set(By Val value As Type) p Validating Type = value End Set End Property End Class The next step is the Masked Edit Cell class. Most of the code required to implement the methods and properties is fairly straight forward. Editing Control Wants Input Key Return True End Function Public Sub Prepare Editing Control For Edit(By Val select All As Boolean) Implements _ IData Grid View Editing Control.It overrides the Initialize Editing Control method to allow the Mask, Prompt Char, and Validating Type properties from the column class to be passed onto the Cell class. Class Masked Edit Editing Control Inherits Masked Text Box Implements IData Grid View Editing Control Private data Grid View Control As Data Grid View Private value Is Changed As Boolean = False Private row Index Num As Integer Public Sub New() End Sub Public Property Editing Control Formatted Value() As Object Implements _ IData Grid View Editing Control. Prepare Editing Control For Edit ' No preparation needs to be done.For example, if a user types in alpha characters (like "abc") into a numeric field, a data conversion error occurs before Row Validation.In this case we need a "global" error checker to detect data conversion errors.