DataAnnotations:递归验证整个对象图 [英] DataAnnotations: Recursively validating an entire object graph

问题描述

我有一个带有 DataAnnotation 属性的对象图，其中对象的某些属性是类，这些类本身具有验证属性，等等.

I have an object graph sprinkled with DataAnnotation attributes, where some properties of objects are classes which themselves have validation attributes, and so on.

在以下场景中:

public class Employee
{
    [Required]
    public string Name { get; set; }

    [Required]
    public Address Address { get; set; }
}

public class Address
{
    [Required]
    public string Line1 { get; set; }

    public string Line2 { get; set; }

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

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

如果我尝试验证 Employee 的 Address 而 PostalCode 没有值，那么我希望(并期望)一个异常，但我没有.这是我的做法:

If I try to validate an Employee's Address with no value for PostalCode, then I would like (and expect) an exception, but I get none. Here's how I'm doing it:

var employee = new Employee
{
    Name = "Neil Barnwell",
    Address = new Address
    {
        Line1 = "My Road",
        Town = "My Town",
        PostalCode = "" // <- INVALID!
    }
};

Validator.ValidateObject(employee, new ValidationContext(employee, null, null));

Validator 还有哪些其他选项可以确保所有属性递归得到验证?

What other options do I have with Validator that would ensure all properties are validated recursively?

推荐答案

这是选择加入属性方法的替代方法.我相信这将正确遍历对象图并验证所有内容.

Here's an alternative to the opt-in attribute approach. I believe this will traverse the object-graph properly and validate everything.

public bool TryValidateObjectRecursive<T>(T obj, List<ValidationResult> results) {

bool result = TryValidateObject(obj, results);

var properties = obj.GetType().GetProperties().Where(prop => prop.CanRead 
    && !prop.GetCustomAttributes(typeof(SkipRecursiveValidation), false).Any() 
    && prop.GetIndexParameters().Length == 0).ToList();

foreach (var property in properties)
{
    if (property.PropertyType == typeof(string) || property.PropertyType.IsValueType) continue;

    var value = obj.GetPropertyValue(property.Name);

    if (value == null) continue;

    var asEnumerable = value as IEnumerable;
    if (asEnumerable != null)
    {
        foreach (var enumObj in asEnumerable)
        {
            var nestedResults = new List<ValidationResult>();
            if (!TryValidateObjectRecursive(enumObj, nestedResults))
            {
                result = false;
                foreach (var validationResult in nestedResults)
                {
                    PropertyInfo property1 = property;
                    results.Add(new ValidationResult(validationResult.ErrorMessage, validationResult.MemberNames.Select(x => property1.Name + '.' + x)));
                }
            };
        }
    }
    else
    {
        var nestedResults = new List<ValidationResult>();
        if (!TryValidateObjectRecursive(value, nestedResults))
        {
            result = false;
            foreach (var validationResult in nestedResults)
            {
                PropertyInfo property1 = property;
                results.Add(new ValidationResult(validationResult.ErrorMessage, validationResult.MemberNames.Select(x => property1.Name + '.' + x)));
            }
        }
    }
}

return result;
}

最新代码:https://github.com/reustmd/DataAnnotationsValidatorRecursive

包装:https://www.nuget.org/packages/DataAnnotationsValidator/

另外，我更新了这个解决方案来处理循环对象图.感谢您的反馈.

Also, I have updated this solution to handle cyclical object graphs. Thanks for the feedback.

这篇关于DataAnnotations:递归验证整个对象图的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！