Validating data in vb net
Errors attached property of the bound element during that step in a previous validation procedure are removed. Errors collection is also cleared when a valid value transfer occurs.
WPF ships with two built-in concrete implementations of the object to the Validation.
Similarly, it makes it possible to invalidate a property when setting another property and it also supports setting multiple errors per property and custom error objects of some other type than that contains validation errors for the specified property or for the entire entity.
You should always raise the Errors Changed event whenever the collection returned by the Get Errors method changes.
Correspondingly, an underlying data value in the view model is automatically updated when the user modifies the bound value in the view.
could not be converted” when the conversion of the string value to an int fails, you may want to customize it.
You can do this by implementing a custom validation rule and associate this with the object at any given step, any errors that were added to the Validation.
Errors collection when an exception is thrown in the setter of the source property.
For example, it would be useful if the Age property of the view model was constrained to only accept values between 10 and 100 and threw an exception if the value was outside of this range: interface.