date validation

Question

how we used data validation on asp.net? date can't be insert greater than the current date.

Answer 1

Use a CompareValidator. Most people use this for comparing two values entered into two textboxes, but you can also use it to compare one entered value with a set value as in your case.

  <asp:CompareValidator id="Compare1" 
       ControlToValidate="TextBox1"
       Type="Date"
       runat="server"/>

In the code behind set Compare1.ValueToCompare = new DateTime(...); and Compare1.Operator = ValidationCompareOperator.LessThanEqual;

Also, Remember: You should always validate on the Server as well as the client, because clientside validation is easy to switch off or by-passed. I would suggest you look at Fluent validation for this.

Answer 2

Make use of the CustomValidator will resolve your issues easily.

CustomValidator

or

You can use javascript to validate your date like as following

var myDate=new Date();
myDate.setFullYear(2010,0,14);
var today = new Date();

if (myDate>today)
  {
  alert("Today is before 14th January 2010");
  }
else
  {
  alert("Today is after 14th January 2010");
  }