使用 KnockoutJS 验证插入常规验证警报

Question

我一直在寻找最有效的方法，将常规验证警报"请检查您的提交"放置在字段集上方，而不是在下面编码的警报弹出窗口中。

http://jsfiddle.net/Nz38D/3/

.HTML：

<script id="customMessageTemplate" type="text/html">
    <em class="customMessage" data-bind='validationMessage: field'></em>
</script>
<fieldset>
    <legend>Details</legend>
    <label>First name:
        <input data-bind='value: firstName' />
    </label>
    <label>Last name:
        <input data-bind='value: lastName' />
    </label>
    <div data-bind='validationOptions: { messageTemplate: "customMessageTemplate" }'>
        <label>Email:
            <input data-bind='value: emailAddress' required pattern="@" />
        </label>
</fieldset>
<br>
<button type="button" data-bind='click: submit'>Submit</button>
<br>
<br> <span data-bind='text: errors().length'></span> errors

.JS：

ko.validation.rules.pattern.message = 'Invalid.';
ko.validation.configure({
    decorateElement: true,
    registerExtenders: true,
    messagesOnModified: true,
    insertMessages: true,
    parseInputAttributes: true,
    messageTemplate: null
});
var viewModel =  function() {
    this.firstName = ko.observable().extend({
        minLength: 2,
        maxLength: 10
    });
    this.lastName = ko.observable().extend({
        required: true
    });
    this.emailAddress = ko.observable().extend({ // custom message
        required: {
            message: 'Enter your email address.'
        }
    });
    this.submit = function () {
        if (this.errors().length == 0) {
            alert('Thank you.');
        } else {
            alert('Please check your submission.');
            this.errors.showAllMessages();
        }
    };
    this.errors = ko.validation.group(this);
};
ko.applyBindings(new viewModel());

Answer 1

我插入了一个虚拟元素来保存验证摘要消息，并将其显示绑定到单击函数中的可观察量：http://jsfiddle.net/sx42q/2/

.HTML：

<!-- ko if: displayAlert -->
<p class="customMessage" data-bind="text: validationSummary"></p> <br />
<!-- /ko -->

.JS：

    this.validationSummary = ko.observable("Complete missing fields below:");
    this.displayAlert = ko.observable(false);
    this.submit = function () {
        if (this.errors().length == 0) {
            alert('Thank you.');
        } else {
            this.displayAlert(true);
            this.errors.showAllMessages();
        }