Question

如果第一次验证失败，如何防止执行下一个ValidationAttribute？

例如，如果（类别“ id” <= 0），则不要尝试检查它是否存在。因为现在，当我执行“ PUT / api / categories / -1”时，我得到了：

{
    "id": [
        "id must be greater or equal to 0",
        "Entity with such Id was not found!"
    ]
}

我要阻止进一步验证的方法：

[HttpPut("{id}")]
public ActionResult UpdateCategory([Min(0)][CategoryExists] int id, [FromBody] Category category)
{
    return new OkResult();
    //if (category.Id == 0) {
    //    return new BadRequestObjectResult("Id property is required!");
    //}
    //_context.Category.Update(category);
    //_context.SaveChanges();
}

最小属性

[AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property)]
public class MinAttribute : ValidationAttribute
{
    private int _minVal;

    public MinAttribute(int minVal)
    {
        _minVal = minVal;
    }

    public override bool IsValid(object value)
    {
        if ((int)value >= _minVal)
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    public override string FormatErrorMessage(string name)
    {
        return $"{name} must be greater or equal to {_minVal}";
    }
}

CategoryExists属性

public class CategoryExistsAttribute : ValidationAttribute
{
    public CategoryExistsAttribute()
    {
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var context = (TechDbContext)validationContext.GetService(typeof(TechDbContext));
        var result = from i in context.Category
                        where i.Id == (int)value
                        select i;
        Category category = result.SingleOrDefault();
        if (category == null)
        {
            return new ValidationResult("Entity with such Id was not found!");
        }

        return ValidationResult.Success;
    }

    public override string FormatErrorMessage(string name)
    {
        return base.FormatErrorMessage(name);
    }
}

Answer 1

为Category对象编写扩展方法，以验证您的所有需求。

例如

internal static bool Validate(this Category category){
if (category.Id <= 0) {
  return false;
    }
  // Add more validations or throw exceptions if needed.
  return true;
}

因此，您可以从控制器中执行此操作。

if(category.Validate()){
  //proceed to other business logic
}

有关数据验证的更多详细信息，请阅读this

防止在错误时执行下一个ValidationAttributes

1 个答案: