idataerrorinfo

If my domain objects implement IDataErrorInfo, and I am using M-V-VM, how do I propagate errors through the ViewModel into the View? If i was binding directly to the model, I would set the "ValidateOnExceptons" and "ValidateOnErrors" properties to true on my binding. But my ViewModel doesn't implement IDataErrorInfo. Only my model. What do I do? Clarification I am dealing with an existing codebase that implements IDataErrorInfo in the domain objects. I can't just implement IDataErrorInfo in the my view model. You can implement IDataErrorInfo additionally in your VM and route the calls to the

I've got a simple address entry app that I'm trying to use the IDataErrorInfo interface as explained on the asp.net site . It works great for items that can be validated independently, but not so well when some items depend on others. For example, validating the postal code depends on the country: private string _PostalCode; public string PostalCode { get { return _PostalCode; } set { switch (_Country) { case Countries.USA: if (!Regex.IsMatch(value, @"^[0-9]{5}$")) _errors.Add("PostalCode", "Invalid Zip Code"); break; case Countries.Canada: if (!Regex.IsMatch(value, @"^([a-z][0-9][a-z]) ?([0-9

I have a TextBox bound to a property of an object which implements IDataErrorInfo . I set up the Validation.ErrorTemplate of the TextBox , and it works fine. The problem is that I have these on a TabControl , and the validation template doesn't display any more if I change the tab to another one and then come back to the initial tab (where the TextBox is). It looks like it is validated(like the value is correct), but actually it is not. This is the IDataErrorInfo object - note that a "correct" value is a string with a length of 2: public class Presenter : IDataErrorInfo { public Presenter() {

I have two date fields: StartDate and EndDate. StartDate must be earlier than EndDate. If the user changes the StartDate to something greater than the EndDate, a red border appears around that DatePicker, and vise versa. If the user changes the 2nd box so that the date range is now correct, the 1st box still has the Validation Error. How can I validate both date fields when either one of them changes? I'm using IDataErrorInfo public string GetValidationError(string propertyName) { switch (propertyName) { case "StartDate": if (StartDate > EndDate) s = "Start Date cannot be later than End Date";

So I have a WPF DataGrid , which is bound to an ObservableCollection . The collection has validation on its members, through IDataErrorInfo . If I edit a cell in a way so as to be invalid, and then tab away from it before hitting enter, then come back and make it valid, the cell will stop showing invalid, however, the "!" at the head of the row will still be there, and the ToolTip will reference the previous, invalid value. Not using Mode=TwoWay for DataGridTextColumns solves one version of the problem, however it seems that this problem can appear out of nowhere for other reasons as well.