以编程方式更改验证范围(MVC3 ASP.NET)

Question

假设我有这个视图模型:

    public class MyModel
    {
        [Range(0, 999, ErrorMessage = "Invalid quantity")]
        public int Quantity { get; set; }
    }

现在,对于此模型的特定实例,有效值的范围将更改:某些可能不会为0,有些可能不会高于5.有效范围的最小值/最大值来自数据库,可以随时更改.

如何动态更改RangeAttribute的最小/最大属性？或者它是验证我的场景的最佳方式？

Answer 1

根据这一点,你可能更喜欢你的......

视图模型:

public class ViewModel
{
    public DateTime MinDate {get; set;}
    public DateTime MaxDate {get; set;}

    [DynamicRange("MinDate", "MaxDate", ErrorMessage = "Value must be between {0} and {1}")]
    public DateTime Date{ get; set; }
}

图书馆类或其他地方:

public class DynamicRange : ValidationAttribute, IClientValidatable
    {
        private readonly string _minPropertyName;
        private readonly string _maxPropertyName;

    public DynamicRange(string minPropName, string maxPropName)
    {
        _minPropertyName = minPropName;
        _maxPropertyName = maxPropName;
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var minProperty = validationContext.ObjectType.GetProperty(_minPropertyName);
        var maxProperty = validationContext.ObjectType.GetProperty(_maxPropertyName);

        if(minProperty == null)
            return new ValidationResult(string.Format("Unknown property {0}", _minPropertyName));

        if (maxProperty == null)
            return new ValidationResult(string.Format("Unknown property {0}", _maxPropertyName));

        var minValue = (int) minProperty.GetValue(validationContext.ObjectInstance, null);
        var maxValue = (int) maxProperty.GetValue(validationContext.ObjectInstance, null);

        var currentValue = (int) value;

        if (currentValue <= minValue || currentValue >= maxValue)
        {
            return new ValidationResult(string.Format(ErrorMessage, minValue, maxValue));
        }

        return null;
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var rule = new ModelClientValidationRule
            {
                ValidationType = "dynamicrange",
                ErrorMessage = ErrorMessage
            };

        rule.ValidationParameters["minvalueproperty"] = _minPropertyName;
        rule.ValidationParameters["maxvalueproperty"] = _maxPropertyName;
        yield return rule;
    }

来自:MVC不显眼的范围验证动态值