Data Binding Error Handling
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow error handling data from server the company Business Learn more about hiring developers or posting ads with us Stack error handling data from server razberry Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of binding error sql 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Data Binding Error Handling in Spring MVC up vote 3 down vote favorite 2 I have a question about data binding in Spring MVC. I have a Controller which accepts a JSON request in the form of @RequestBody. I have all the JSR 303 validations in place and it works like a charm. JSON Request public class TestJSONRequest { @Size(min=10,message="{invalid.demo.size}") String demo; int code; } Controller @Controller @RequestMapping("/test") public class TestController { public void testEntry(@RequestBody TestJSONRequest jsonRequest,ModelMap map) Set
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a http://stackoverflow.com/questions/11730567/data-binding-error-handling-in-spring-mvc minute: Sign up Catch error in GridView automatic databinding up vote 0 down vote favorite I have a gridview with a DataSourceID set, so the databinding happens automatically. The problem is that sometimes, the procedure defined in the SqlDataSource takes a very long time to finish, so the binding comes with a timeout expired error. How can I catch this error without http://stackoverflow.com/questions/1018496/catch-error-in-gridview-automatic-databinding manually databinding the gridview and surrounding it with try/catch statements? asp.net data-binding gridview error-handling share|improve this question asked Jun 19 '09 at 15:09 add a comment| 4 Answers 4 active oldest votes up vote 4 down vote If an exception occurs when the SqlDataSource is executing, it fires its appropriate post-action event - Selected, in this case. You can optionally create an event handler for this event and in the event handler say that you've handled the exception. This diagram shows how this interaction works with the ObjectDataSource (the concept is the same with the SqlDataSource control). When examining the diagram below, replace the words "ObjectDataSource" with "SqlDataSource" and "Underlying Object" with "Database" to have it be pertinent for the SqlDataSource. As you can see, the Selecting event is raised before the data is sent off to the database and the Selected event is raised after the data comes back (or if there's an exception). You can create a Selected event handler in your page and check to see if an exception occurred and decide whether you want to handle it yourself. Fre
All Products Customers Pricing Developers Support Developer Support Consulting Partners Consulting Services Contact Sales Resources Blog FAQ Partners Webinars About Xamarin Blog About Xamarin Questions Best Of... Sign In · Register Welcome Guides Recipes APIs Samples https://forums.xamarin.com/discussion/27082/data-binding-error-handling Forums Components Videos Forum › Xamarin Platform › Xamarin.Forms Categories Recent Threads Activity Best Of... Unanswered Data binding error handling? DarrelLiu Darrel LiuUSMember ✭ October 2014 edited October 2014 in Xamarin.Forms What's a pattern for handling errors with data binding, for example, when user input can't be converted to model's required type? I can't find anything in IValueConverter that could help identify target type/property. In my case, I actually want error handling to show the error on the UI. Thanks. 0 Posts adamkemp Adam Kemp USInsider, Developer Group Leader mod October 2014 Put the validation in your ViewModel and expose a property like IsValid or IsInvalid. You can also expose a property for an error message. Use bindings to show and hide error messages or mark the UI in some way to show that there is a problem. 0 DarrelLiu Darrel Liu USMember error handling data ✭ October 2014 If my ViewModel takes an int, and the user inputs a string, then Binding won't be able to assign the value to ViewModel. Unless I intercept this with a ValueConverter, I see no way my code will be aware of the error. 0 adamkemp Adam Kemp USInsider, Developer Group Leader mod October 2014 Your ViewModel in that case should take a string, and it should detect the invalid format and report it like I described. The Model may take an int, though. The role of the ViewModel is to keep track of this kind of intermediate state that is valid for the View but not for the Model. The ViewModel can push the state to the Model once it becomes valid to do so (like when all of the data is sane). 0 DarrelLiu Darrel Liu USMember ✭ October 2014 I see. I was looking for more of a built-in way to do this. 0 adamkemp Adam Kemp USInsider, Developer Group Leader mod October 2014 The only way to do it without involving the view model would be if you had a view which didn't allow invalid values to be entered in the first place. You could, for instance, write a custom renderer that filtered new characters