.NET MVC 自定义日期验证器

Question

明天我将为我正在工作的会议应用程序编写一个自定义日期验证类，该应用程序将验证给定的开始或结束日期是否 A) 小于当前日期，或 B) 开始日期大于会议的结束日期（反之亦然）。

我认为这可能是一个相当普遍的要求。谁能指出我的博客文章的方向，这可能会帮助我解决这个问题？

我使用的是 .net 3.5，所以我不能使用 .NET 4 中内置的新模型验证器 api。我正在处理的项目是 MVC 2。

更新：我正在编写的类需要扩展 System.ComponentModel.DataAnnotations 命名空间。在 .NET 4 中有一个可以实现的 IValidateObject 接口，这使得这种事情绝对是轻而易举，但遗憾的是我不能使用 .Net 4。我如何在 .Net 3.5 中做同样的事情？

Answer 1

public sealed class DateStartAttribute : ValidationAttribute
{
    public override bool IsValid(object value)
    {
        DateTime dateStart = (DateTime)value;
        // Meeting must start in the future time.
        return (dateStart > DateTime.Now);
    }
}

public sealed class DateEndAttribute : ValidationAttribute
{
    public string DateStartProperty { get; set; }
    public override bool IsValid(object value)
    {
        // Get Value of the DateStart property
        string dateStartString = HttpContext.Current.Request[DateStartProperty];
        DateTime dateEnd = (DateTime)value;
        DateTime dateStart = DateTime.Parse(dateStartString);

        // Meeting start time must be before the end time
        return dateStart < dateEnd;
    }
}

在您的视图模型中：

[DateStart]
public DateTime StartDate{ get; set; }

[DateEnd(DateStartProperty="StartDate")]
public DateTime EndDate{ get; set; }

在您的操作中，只需检查 ModelState.IsValid。这就是你所追求的？

Answer 2

我知道这篇文章比较老，但是，我找到的这个解决方案要好得多。

如果对象是视图模型的一部分时具有前缀，则本文中接受的解决方案将不起作用。

即线条

// Get Value of the DateStart property
string dateStartString = HttpContext.Current.Request[DateStartProperty];

可以在这里找到更好的解决方案： ASP .NET MVC 3 Validation using Custom DataAnnotation Attribute:

新的DateGreaterThan 属性：

public sealed class DateGreaterThanAttribute : ValidationAttribute
{
    private const string _defaultErrorMessage = "'{0}' must be greater than '{1}'";
    private string _basePropertyName;

    public DateGreaterThanAttribute(string basePropertyName) : base(_defaultErrorMessage)
    {
        _basePropertyName = basePropertyName;
    }

    //Override default FormatErrorMessage Method
    public override string FormatErrorMessage(string name)
    {
        return string.Format(_defaultErrorMessage, name, _basePropertyName);
    }

    //Override IsValid
    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        //Get PropertyInfo Object
        var basePropertyInfo = validationContext.ObjectType.GetProperty(_basePropertyName);

        //Get Value of the property
        var startDate = (DateTime)basePropertyInfo.GetValue(validationContext.ObjectInstance, null);

        var thisDate = (DateTime)value;

        //Actual comparision
        if (thisDate <= startDate)
        {
            var message = FormatErrorMessage(validationContext.DisplayName);
            return new ValidationResult(message);
        }

        //Default return - This means there were no validation error
        return null;
    }
}

使用示例：

[Required]
[DataType(DataType.DateTime)]
[Display(Name = "StartDate")]
public DateTime StartDate { get; set; }

[Required]
[DataType(DataType.DateTime)]
[Display(Name = "EndDate")]
[DateGreaterThanAttribute("StartDate")]
public DateTime EndDate { get; set; }

Answer 3

我认为应该这样做：

public boolean MeetingIsValid( DateTime start, DateTime end )
{
      if( start < DateTime.Now || end < DateTime.Now )
          return false;

      return start > end || end < start;
}

Answer 4

public ActionResult Index(vmemployee vme)

    {

        emplyee emp = new emplyee();
        vme.cities = new List<city>();

        vme.countries = new List<country>();

        vme.departments = new List<department>();

        Hrcontext context = new Hrcontext();
        vme.countries = context.cntentity.ToList();
        vme.cities = context.cityentity.ToList();
        vme.departments = context.deptentity.ToList();

        return View("employeelist", vme);
    }

    public ActionResult Index1(vmemployee vm)
    {

        vm.liemp = new List<emplyee>();
        return View("Searchemployee", vm);

    }
    [submit(Name = "sav")]
    public ActionResult save(vmemployee vme)
    {
        vme.cities = new List<city>();
        vme.countries = new List<country>();
        vme.departments = new List<department>();



        Hrcontext context = new Hrcontext();
        vme.countries = context.cntentity.ToList();
        vme.cities = context.cityentity.ToList();
        vme.departments = context.deptentity.ToList();
        vme.emp.Imagefile.SaveAs(@"C:\inetpub\wwwroot\hrsestem\hrsestem\images\" + vme.emp.Imagefile.FileName);
        vme.emp.Imagepath= (@"C:\inetpub\wwwroot\hrsestem\hrsestem\images\" + vme.emp.Imagefile.FileName);

        if (ModelState.IsValid == true)
        {
            context.empentity.Add(vme.emp);
            context.SaveChanges();
        }
        return View("employeelist", vme);
    }

Answer 5

public ActionResult Index()
    {
        
        return View("department1");
    }
    public ActionResult Savedata(Vmdepartment vm)
    {

        Hrcontext context = new Hrcontext();
        context.deptentity.Add(vm.dept);
        context.SaveChanges();

        return View("department1", vm);
    }
    public ActionResult Index1(Vmdepartment vm)
    {
        vm.liDepartment = new List<department>();
        
        return View("departmentview",vm);
    }

    public ActionResult search(Vmdepartment vm) {
        var n = vm.dept.name;
        vm.liDepartment = new List<department>();
        Hrcontext context = new Hrcontext();
        vm.liDepartment = context.deptentity.Where(a => a.name == n).ToList();
        return View("departmentview",vm);

    }
}