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Knockout Validation evaluates immediately on load

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I'm using MVC, Knockout, and Knockout Validation to validate my view model.

I'm running into an issue where the validation for view model properties are firing immediately upon loading. In other words, "This field is required" shows up next to my inputs before a user has attempted to change their values.

This problem is specifically happening with dropdown (select) controls.

I'm guessing that this is a problem that I've created by somehow unintentionally changing/accessing/mutating the observable in another part of my javascript code. However, I don't know how to track this down.

Is there a way that I can somehow subscribe or track the even that fires that causes validation in Knockout Validation? I just need to know why this is firing in the way it is. I'm pretty confident that the value of the isValid() function is consistently false.

Here's a sample of how my HTML is setup on page load, unmolested:

<select class="highlightable validationElement" name="obsstate" data-bind="value: standardAnswers.ans106_1.value" required="true">     <option value="">-- Select -- </option>         <option value="AK">AK</option>         <option value="AL">AL</option>         etc...  </select> 

As displayed on my local machine

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letsgetsilly Avatar asked Dec 03 '12 20:12

letsgetsilly


2 Answers

After applying the bindings for the viewmodel. Then for that viewmodel make showAllMessages as false

Example

YourViewmodelname.errors.showAllMessages(false); 
like image 96
Velmurugan Avatar answered Oct 13 '22 22:10

Velmurugan


Quoting KO page.... ( http://knockoutjs.com/documentation/options-binding.html )

KO will prefix the list of items with one that displays the text “Select an item…” and has the value undefined. So, if myChosenValue holds the value undefined (which observables do by default), then the dummy option will be selected. If the optionsCaption parameter is an observable, then the text of the initial item will update as the observable’s value changes.

So, I solved it by setting "undefined" when defining the property, see example below:

self.myProperty = ko.observable(undefined).extend({     required :  {"Field Required"} }); 

Hope this helps...

like image 30
Francisco Avatar answered Oct 14 '22 00:10

Francisco