DXValidationProvider.Validate(Control) Method

Validates the specified editor associated with the DXValidationProvider.

Namespace: DevExpress.XtraEditors.DXErrorProvider

Assembly: DevExpress.XtraEditors.v24.1.dll

NuGet Package: DevExpress.Win.Navigation

Declaration

C#

public bool Validate(
    Control control
)

VB.NET

Public Function Validate(
    control As Control
) As Boolean

Parameters

Name	Type	Description
control	Control	A Control object or descendant that represents the editor to be validated.

Returns

Type	Description
Boolean	true if the editor is successfully validated; otherwise, false.

Remarks

Call the Validate method to validate the specified control. To validate controls automatically, set the ValidationMode property to Auto.

Example

This example demonstrates how to validate data via the DXValidationProvider component. In this example, validation rules (built-in and custom) are created in code, and associated with editors using the DXValidationProvider.SetValidationRule method.

The CustomValidationRule class represents a custom validation rule that checks whether the editor’s value begins with “Dr.”, “Mr.”, “Mrs.”, “Miss” or “Ms.”.

C#

using DevExpress.XtraEditors.DXErrorProvider;

// Validates the editors when a user presses/clicks the OK button.
dxValidationProvider1.ValidationMode = ValidationMode.Manual;

// ...
ConditionValidationRule containsValidationRule = new ConditionValidationRule();
containsValidationRule.ConditionOperator = ConditionOperator.Contains;
containsValidationRule.Value1 = '@';
containsValidationRule.ErrorText = "Please enter a valid email";
containsValidationRule.ErrorType = ErrorType.Warning;

CompareAgainstControlValidationRule compValidationRule = 
    new CompareAgainstControlValidationRule();
compValidationRule.Control = notEmptyTextEdit;
compValidationRule.CompareControlOperator = CompareControlOperator.Equals;
compValidationRule.ErrorText = "Please enter a value that equals to the first editor's value";
compValidationRule.CaseSensitive = true;

CustomValidationRule customValidationRule = new CustomValidationRule();
customValidationRule.ErrorText = "Please enter a valid person name";
customValidationRule.ErrorType = ErrorType.Warning;

dxValidationProvider1.SetValidationRule(containsTextEdit, containsValidationRule);
dxValidationProvider1.SetValidationRule(compareTextEdit, compValidationRule);
dxValidationProvider1.SetValidationRule(customTextEdit, customValidationRule);


private void buttonOk_Click(object sender, EventArgs e) {
    dxValidationProvider1.Validate();
}

// Implements a custom validation rule.
public class CustomValidationRule : ValidationRule {
    public override bool Validate(Control control, object value) {
        string str = (string)value;
        string[] values = new string[] { "Dr.", "Mr.", "Mrs.", "Miss", "Ms." };
        foreach(string val in values) {
            if(ValidationHelper.Validate(str, ConditionOperator.BeginsWith, 
                val, null, null, false)) {
                string name = str.Substring(val.Length);
                if(name.Trim().Length > 0) return true;
            }
        }
        return false;
    }
}

VB.NET

Imports DevExpress.XtraEditors.DXErrorProvider

' Validates the editors when a user presses/clicks the OK button.
dxValidationProvider1.ValidationMode = ValidationMode.Manual
' ...
Dim containsValidationRule As New ConditionValidationRule()
containsValidationRule.ConditionOperator = ConditionOperator.Contains
containsValidationRule.Value1 = "@"
containsValidationRule.ErrorText = "Please enter a valid email"
containsValidationRule.ErrorType = ErrorType.Warning

Dim compValidationRule As New CompareAgainstControlValidationRule()
compValidationRule.Control = notEmptyTextEdit
compValidationRule.CompareControlOperator = CompareControlOperator.Equals
compValidationRule.ErrorText = "Please enter a value that equals to the first editor's value"
compValidationRule.CaseSensitive = True

Dim customValidationRule As New CustomValidationRule()
customValidationRule.ErrorText = "Please enter a valid person name"
customValidationRule.ErrorType = ErrorType.Warning

dxValidationProvider1.SetValidationRule(containsTextEdit, containsValidationRule)
dxValidationProvider1.SetValidationRule(compareTextEdit, compValidationRule)
dxValidationProvider1.SetValidationRule(customTextEdit, customValidationRule)

Private Sub ButtonOK_Click(sender As Object, e As EventArgs) Handles ButtonOK.Click
    dxValidationProvider1.Validate()
End Sub


' Implements a custom validation rule.
Public Class CustomValidationRule
    Inherits ValidationRule

    Public Overrides Function Validate(ByVal control As Control, ByVal value As Object) As Boolean
        Dim str As String = DirectCast(value, String)
        Dim values() As String = { "Dr.", "Mr.", "Mrs.", "Miss", "Ms." }
        For Each val As String In values
            If ValidationHelper.Validate(str, ConditionOperator.BeginsWith, val, Nothing, Nothing, False) Then
                Dim name As String = str.Substring(val.Length)
                If name.Trim().Length > 0 Then
                    Return True
                End If
            End If
        Next val
        Return False
    End Function
End Class