ValidationSummary

in namespace DotVVM.Framework.Controls

Displays all validation messages from the current Validation.Target.

Usage & Scenarios

Displays all validation errors in a list.

Look at the Validation tutorial to see how the validation works.

Sample 1: Basic ValidationSummary

The ValidationSummary will display all validation errors in the validation context.

page.dothtml
ViewModel.cs

<dot:TextBox Text="{value: Text}" />

<dot:ValidationSummary />

<dot:Button Text="SEND" Click="{command: Send()}" />

using System.ComponentModel.DataAnnotations;

namespace DotvvmWeb.Views.Docs.Controls.builtin.ValidationSummary.sample1
{
    public class ViewModel
    {
        [Required]
        public string Text { get; set; }

        public void Send()
        {
            // process data
        }
    }
}

Sample 2: Validation errors from child objects

By default, the ValidationSummary control displays errors that comes directly from the Validation.Target object's properties. If the validation target contains another child objects, the validation errors from those objects are not displayed. This is because of performance reasons.

However, using the IncludeErrorsFromChildren property, you can tell the control to display validation errors event from the child objects. Just be careful because there will be a performance penalty if you use this feature on large and complicated viewmodels.

page.dothtml
ViewModel.cs

<dot:TextBox Text="{value: ChildObject.Text}" />

<dot:ValidationSummary IncludeErrorsFromChildren="true" />

<dot:Button Text="SEND" Click="{command: Send()}" />

using System.ComponentModel.DataAnnotations;

namespace DotvvmWeb.Views.Docs.Controls.builtin.ValidationSummary.sample2
{
    public class ViewModel
    {
        public ChildViewModel ChildObject { get; set; } = new ChildViewModel();

        public void Send()
        {
            // process data
        }
    }

    public class ChildViewModel
    {
        [Required]
        public string Text { get; set; }
    }
}

Sample 3: Validation errors from the `Validation.Target`

You can also tell the ValidationSummary control to display validation errors attached directly to the Validation.Target itself using the IncludeErrorsFromTarget property.

The sample below creates a server-side validation error using the IValidatableObject interface.

page.dothtml
ViewModel.cs

<dot:TextBox Text="{value: ChildObject.Text1}" />
<dot:TextBox Text="{value: ChildObject.Text2}" />

<dot:ValidationSummary IncludeErrorsFromTarget="true"
                       Validation.Target="{value: ChildObject}"/>

<dot:Button Text="SEND" Click="{command: Send()}" />

using DotVVM.Framework.ViewModel;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;

namespace DotvvmWeb.Views.Docs.Controls.builtin.ValidationSummary.sample3
{
    public class ViewModel
    {
        public ChildViewModel ChildObject { get; set; } = new ChildViewModel();

        public void Send()
        {
            // process data
        }
    }

    public class ChildViewModel : IValidatableObject
    {
        [Required]
        public string Text1 { get; set; }

        [Required]
        public string Text2 { get; set; }

        public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
        {
            if (Text1 != Text2)
            {
                yield return new ValidationResult("This ChildViewModel is not valid.");
            }
        }
    }
}

Properties

Name	Type	Description	Notes	Default Value
Attributes	Dictionary<String,Object>		attribute inner element static value bindable default	null
ClientIDMode	ClientIDMode	Gets or sets the client ID generation algorithm.	attribute inner element static value bindable default	Static
DataContext	Object	Gets or sets a data context for the control and its children. All value and command bindings are evaluated in context of this value.	attribute inner element static value bindable default	null
ID	String	Gets or sets the unique control ID.	attribute inner element static value bindable default	null
IncludeErrorsFromChildren	Boolean	Gets or sets whether the errors from child objects in the viewmodel will be displayed too.	attribute inner element static value bindable default	False
IncludeErrorsFromTarget	Boolean	Gets or sets whether the errors from the TargetProperty object will be displayed too.	attribute inner element static value bindable default	False
InnerText	String	Gets or sets the inner text of the HTML element.	attribute inner element static value bindable default	null
Visible	Boolean	Gets or sets whether the control is visible.	attribute inner element static value bindable default	True

HTML produced by the control

This control renders the HTML unordered list.

<ul data-bind="foreach: ...">
  <li data-bind="..."></li>
</ul>