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This article is about how to write form validation code when you use AngularJS/HTML5.

HTML5 Form Validation(required)

<form name="sampleform">
	<input type="text" name="fk" placeholder="First Keywords" pattern="[a-zA-z]" title="AAAAAAAAAAAAAA" required />
	<input type="text" name="sk" placeholder="Second Keywords" pattern="[a-zA-z]" title="BBBBBBBBBBBBBB" required />
	<input type="submit" value="Submit!"  required />
</form>

If you want to disable the HTML5 form validation, add "novalidate". (such as when you use the validation in the function of AngularJS)

<form name="sampleform" novalidate>

If you want to activate the submit button although have the "required" input, add a "formnovalidate".

<input type="submit" value="Submit!" formnovalidate />

AngularJS Form Validation

First,if you do not write "ng-model", form validation of AngularJS will not work.

<form name="sampleform" ng-controller="SampleCtrl" ng-submit="submit()" novalidate>

	<label>
		<input type="text" name="fk" ng-model="sample.fk" placeholder="First Keywords" required ng-pattern="/^[a-zA-z]*$/" ng-trim="false" />
	</label>
	<div class="error" ng-show="sampleform.$invalid">
		<small class="error" ng-show="sampleform.fk.$error.required">Required!</small>
		<small class="error" ng-show="sampleform.fk.$error.pattern">Alphabet Words Only!</small>
	</div>

	<label>
		<input type="text" name="sk" ng-model="sample.sk" placeholder="Second Keywords" required ng-pattern="/^[a-zA-z]*$/" ng-trim="false" />
	</label>
	<div class="error" ng-show="sampleform.$invalid">
		<small class="error" ng-show="sampleform.sk.$error.required">Required!</small>
		<small class="error" ng-show="sampleform.sk.$error.pattern">Alphabet Words Only!</small>
	</div>

	<input type="submit" ng-disabled="!sampleform.$valid" value="Generate!" required />
	<!-- start test -->
	<p>{{sampleform.$valid}}</p>
	<p>{{sampleform.$dirty}}</p>
	<!-- end test -->
</form>

By adding a "novalidate" to form, you can avoid conflict validation of HTML5 and AngularJS .

There is also a method using the "ng-messages" to display the validation error, but in the above sample using ng-show.

By setting the "ng-disabled" to submit button, you can avoid active when the validation error has occurred.