Business Validation with ObjectGraphDataAnnotationsValidator with complex type model - blazor-server-side

Question

In my blazor server application i have done business validation based on this
#page "/"
#inherits IndexBase
<EditForm Model="#MyModel" OnValidSubmit="#HandleValidSubmit">
<ObjectGraphDataAnnotationsValidator />
<CustomValidator #ref="customValidator" />
<ValidationSummary />
<div>
<InputText #bind-Value="MyModel.Customer.Name"></InputText>
<ValidationMessage For="()=>MyModel.Customer.Name" />
</div>
<div>
<InputNumber #bind-Value="MyModel.Customer.Age"> </InputNumber>
<ValidationMessage For="()=>MyModel.Customer.Age" />
</div>
<button Text="Save" type="submit">Get Result</button>
</EditForm>
and its base class conatains
public class IndexBase:ComponentBase
{
protected MyModel MyModel { get; set; } = new MyModel();
protected CustomValidator customValidator;
protected void HandleValidSubmit()
{
customValidator.ClearErrors();
var errors = new Dictionary<string, List<string>>();
if ( MyModel.Customer.Name.ToLower().StartsWith("a"))
{
errors.Add("Customer.Age", new List<string>() { "Age should be greater than 10" });
}
if (errors.Count() > 0)
{
customValidator.DisplayErrors(errors);
}
else
{
// Process the form
}
}
}
and MyModel looks like
public class MyModel
{
[ValidateComplexType]
public Customer Customer { get; set; } = new Customer();
}
public class Customer
{
[Required]
public string Name { get; set; }
public int Age { get; set; }0
}
and my CustomValidator looks like below code (from here)
public class CustomValidator : ComponentBase
{
private ValidationMessageStore messageStore;
[CascadingParameter]
private EditContext CurrentEditContext { get; set; }
protected override void OnInitialized()
{
if (CurrentEditContext == null)
{
throw new InvalidOperationException(
$"{nameof(CustomValidator)} requires a cascading " +
$"parameter of type {nameof(EditContext)}. " +
$"For example, you can use {nameof(CustomValidator)} " +
$"inside an {nameof(EditForm)}.");
}
messageStore = new ValidationMessageStore(CurrentEditContext);
CurrentEditContext.OnValidationRequested += (s, e) =>
messageStore.Clear();
CurrentEditContext.OnFieldChanged += (s, e) =>
messageStore.Clear(e.FieldIdentifier);
}
public void DisplayErrors(Dictionary<string, List<string>> errors)
{
foreach (var err in errors)
{
FieldIdentifier x = CurrentEditContext.Field(err.Key);
messageStore.Add(x, err.Value);
}
CurrentEditContext.NotifyValidationStateChanged();
}
public void ClearErrors()
{
messageStore.Clear();
CurrentEditContext.NotifyValidationStateChanged();
}
}
When i click submit button validation code works, but does not adding modified invalid class to input control. So this does not display error message and red border to control

Answer 1

I can do like this..
protected void HandleValidSubmit()
{
customValidator.ClearErrors();
var errors = new Dictionary<FieldIdentifier, List<string>>();
if ( MyModel.Customer.Name.ToLower().StartsWith("a"))
{
errors.Add(new FieldIdentifier(MyModel.Customer, "Name"), new
List<string> { "Age should be greater than 10" });
}
if (errors.Count() > 0)
{
customValidator.DisplayErrors(errors);
}
else
{
// Process the form
}
}
and changed the parameter type in DisplayErrors method like this,
public void DisplayErrors(Dictionary<FieldIdentifier, List<string>> errors)
{
foreach (var err in errors)
{
messageStore.Add(err.Key, err.Value);
}
CurrentEditContext.NotifyValidationStateChanged();
}