aiexandr / caliburn.micro.validation Goto Github PK

A manual call to Validate doesn't cause my bound controls validation errors to update.

Is possibile to scan the [MaxLength] and [Require] attribute from object and build validation rule?

protected void AutoBuildValidationRulesForObject<T>(T obj, string variableName)
        {


            foreach (var field in typeof(T).GetProperties())
            {
var maxLenghtAttr = (MaxLengthAttribute)field.GetCustomAttributes(typeof(MaxLengthAttribute), true).ToList().FirstOrDefault();
                var required = (ValidationAttribute)field.GetCustomAttributes(typeof(RequiredAttribute), true).ToList().FirstOrDefault();

                if (maxLenghtAttr != null)
                {


                    var variable = Expression.Variable(typeof(T), variableName);
                    var pe = Expression.Property(variable, typeof(T), field.Name);
                    var left = Expression.Property(pe, typeof(string).GetProperty("Length"));
                    var right = Expression.Constant(maxLenghtAttr.Length, typeof(int));
                    var e2 = Expression.LessThanOrEqual(left, right);
                    var predicate = Expression.Lambda<Func<bool>>(e2);
                    if (required != null)
                        AddValidationRule(() => variable).Condition(predicate).Message(required.ErrorMessage);
                    else
                        AddValidationRule(() => variable).Condition(predicate).Message(string.Format("{0} Must be Less then of {1}", field.Name, maxLenghtAttr.Length));
                }

Could you provide an example how to use it in a view (for example using a Textbox)?
Would I need to overwrite the Validation.ErrorTemplate in order to show the error message in my texthox?

Hello,

Can you please give us a simple demo app on which you've implemented this so I can better understand this one, Even one more project is available forked from your project but that also does not contain any examples.
I am very new to this validation field please do the needful.

Ref Git Repo : https://github.com/dingjimmy/Caliburn.Micro.FluentValidation

Thank you,

Some validation rules require async operations such as contacting a web service or database. Please add support for async validation.

How do I check if a validation error still exists?

Is there a property or method that I can use to check for existing validation errors?

It would be very convenient if there is a HasError property (or something similar) that will indicate that there are still validation errors. We can then bind this property to the IsEnabled property of a button and use a converter to invert the value so that the button will only be clickable if there are no validation errors left. Or just return !HasError in the CanButtonName method. 😄

Please make a NuGet package for this project.