Javascript ng-pattern 不显示 $error.pattern
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ng-pattern doesn't show $error.pattern
提问by irom
I have script hereand ng-pattern works correctly because scope.subnet is shown in Output only after input matches pattern. But ng-show doesn't display any error if ng-pattern is not matched
我在这里有脚本并且 ng-pattern 工作正常，因为只有在输入匹配模式后，scope.subnet 才会显示在输出中。但是如果 ng-pattern 不匹配，ng-show 不会显示任何错误
<body ng-contoller="myConfigGenCtr">
<form novalidate name="myForm">
<div class="form-group">
<label for="hostname">Firewall hostname</label>
<input type="text" ng-model="hostname" class="form-control" id="hostname">
</div>
<div class="form-group">
<label for="subnet">Firewall subnet</label>
<input type="text" ng-model="subnet" class="form-control" id="subnet"
required ng-pattern="/^(?:[0-9]{1,3}\.){3}/" >
<div class="custom-error" ng-show="myForm.subnet.$error.pattern">
Not a valid subnet, should be i.e. 10.x.y. (3 bytes only)</div>
</div>
</form>
<div>Output: {{subnet}}</div>
</body>
回答by Pankaj Parkar
When you add form tag with its name, angular does create a scopevariable for that nameattribute value & do add all the form fields of the form which have nameattributes. Those fields attribute variable get created inside form scope object. Like here you are using myFormthat means $scope.myFromhas all the information about the form fields. like its validity using $valid, $invalid, $error, etc.
当您添加带有其名称的表单标签时，angular 会scope为该name属性值创建一个变量并添加具有name属性的表单的所有表单字段。这些字段属性变量是在表单范围对象内创建的。就像这里您使用的myForm那样，这意味着$scope.myFrom拥有有关表单字段的所有信息。喜欢它的有效性使用$valid，$invalid，$error，等。
Here you are using ng-show="myForm.subnet.$error.pattern"on subnetelement of form. You missed to add name="subnet"attribute on input field, that turns out to subnetelement validation doesn't available inside myFormscope variable.
在这里，您正在使用ng-show="myForm.subnet.$error.pattern"的subnet表单元素。您错过了name="subnet"在输入字段上添加属性，结果是subnet元素验证在myForm范围变量内不可用。
Markup
标记
<input type="text" name="subnet" ng-model="subnet" class="form-control"
id="subnet" required ng-pattern="/^(?:[0-9]{1,3}\.){3}/" >
