ASP .NET MVC 3 Data Annotations GreaterThan LowerThan for DateTime and int
I would like to know what is the easiest way to have a "Greater Than" & "Lower Than" validation on a ASP.NET MVC 3 form?
I use unobtrusive JavaScript for client validation. I have two DateTime properties (StartDate & EndDate) and I need a开发者_开发技巧 validation to be sure that the EndDate is greater than the StartDate. I have another similar case with another form on which I have a MinValue (int) & MaxValue (int).
Does this type of validation exist by default? Or does someone know an article which explains how to implement it?
Could look at the dataannotationsextensions it does Min/Max for int
Also have a look at a foolproof validation it inlcudes GreaterThan comparison for numeric/datetime etc
You can simply do this with custom validation.
[AttributeUsage(AttributeTargets.Property, AllowMultiple=true)]
public class DateGreaterThanAttribute : ValidationAttribute
{
string otherPropertyName;
public DateGreaterThanAttribute(string otherPropertyName, string errorMessage)
: base(errorMessage)
{
this.otherPropertyName = otherPropertyName;
}
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
ValidationResult validationResult = ValidationResult.Success;
try
{
// Using reflection we can get a reference to the other date property, in this example the project start date
var otherPropertyInfo = validationContext.ObjectType.GetProperty(this.otherPropertyName);
// Let's check that otherProperty is of type DateTime as we expect it to be
if (otherPropertyInfo.PropertyType.Equals(new DateTime().GetType()))
{
DateTime toValidate = (DateTime)value;
DateTime referenceProperty = (DateTime)otherPropertyInfo.GetValue(validationContext.ObjectInstance, null);
// if the end date is lower than the start date, than the validationResult will be set to false and return
// a properly formatted error message
if (toValidate.CompareTo(referenceProperty) < 1)
{
validationResult = new ValidationResult(ErrorMessageString);
}
}
else
{
validationResult = new ValidationResult("An error occurred while validating the property. OtherProperty is not of type DateTime");
}
}
catch (Exception ex)
{
// Do stuff, i.e. log the exception
// Let it go through the upper levels, something bad happened
throw ex;
}
return validationResult;
}
}
and use it in model like
[DisplayName("Start date")]
[DisplayFormat(DataFormatString = "{0:MM/dd/yyyy}", ApplyFormatInEditMode = true)]
public DateTime StartDate { get; set; }
[DisplayName("Estimated end date")]
[DisplayFormat(DataFormatString = "{0:MM/dd/yyyy}", ApplyFormatInEditMode = true)]
[DateGreaterThan("StartDate", "End Date end date must not exceed start date")]
public DateTime EndDate { get; set; }
This works well with server side validation.For client side validaion you can write the method like GetClientValidationRules like
public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
{
//string errorMessage = this.FormatErrorMessage(metadata.DisplayName);
string errorMessage = ErrorMessageString;
// The value we set here are needed by the jQuery adapter
ModelClientValidationRule dateGreaterThanRule = new ModelClientValidationRule();
dateGreaterThanRule.ErrorMessage = errorMessage;
dateGreaterThanRule.ValidationType = "dategreaterthan"; // This is the name the jQuery adapter will use
//"otherpropertyname" is the name of the jQuery parameter for the adapter, must be LOWERCASE!
dateGreaterThanRule.ValidationParameters.Add("otherpropertyname", otherPropertyName);
yield return dateGreaterThanRule;
}
Now simply in view
$.validator.addMethod("dategreaterthan", function (value, element, params) {
return Date.parse(value) > Date.parse($(params).val());
});
$.validator.unobtrusive.adapters.add("dategreaterthan", ["otherpropertyname"], function (options) {
options.rules["dategreaterthan"] = "#" + options.params.otherpropertyname;
options.messages["dategreaterthan"] = options.message;
});
You can find more details in this link
I don't know if writing your own validator class is the "easiest" way, but that's what I did.
Usage:
<DataType(DataType.Date)>
Public Property StartDate() As DateTime
<DataType(DataType.Date)>
<DateGreaterThanEqual("StartDate", "end date must be after start date")>
Public Property EndDate() As DateTime
Class:
<AttributeUsage(AttributeTargets.Field Or AttributeTargets.Property, AllowMultiple:=False, Inherited:=False)>
Public Class DateGreaterThanEqualAttribute
Inherits ValidationAttribute
Public Sub New(ByVal compareDate As String, ByVal errorMessage As String)
MyBase.New(errorMessage)
_compareDate = compareDate
End Sub
Public ReadOnly Property CompareDate() As String
Get
Return _compareDate
End Get
End Property
Private ReadOnly _compareDate As String
Protected Overrides Function IsValid(ByVal value As Object, ByVal context As ValidationContext) As ValidationResult
If value Is Nothing Then
' no need to do or check anything
Return Nothing
End If
' find the other property we need to compare with using reflection
Dim compareToValue = Nothing
Dim propAsDate As Date
Try
compareToValue = context.ObjectType.GetProperty(CompareDate).GetValue(context.ObjectInstance, Nothing).ToString
propAsDate = CDate(compareToValue)
Catch
Try
Dim dp As String = CompareDate.Substring(CompareDate.LastIndexOf(".") + 1)
compareToValue = context.ObjectType.GetProperty(dp).GetValue(context.ObjectInstance, Nothing).ToString
propAsDate = CDate(compareToValue)
Catch
compareToValue = Nothing
End Try
End Try
If compareToValue Is Nothing Then
'date is not supplied or not valid
Return Nothing
End If
If value < compareToValue Then
Return New ValidationResult(FormatErrorMessage(context.DisplayName))
End If
Return Nothing
End Function
End Class
Take a look at the answer of this thread,
There is a lib called MVC.ValidationToolkit. Though I'm not sure whether it works in case of DateTime fields.
You can use the DateGreaterThanEqual attribute in your model. Here is a snippet of code that I used to validate two fields in my form.
[DataType(DataType.Date)]
[DisplayName("From Date")]
public DateTime? StartDate { get; set; }
[DataType(DataType.Date)]
[DisplayName("To Date")]
[DateGreaterThanEqual("StartDate")]
public DateTime? EndDate { get; set; }
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