javascript MVC 4 使用 jquery 如何检查模型属性中是否有元素
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MVC 4 using jquery how to check if the model property has elements in it
提问by jbolt
I'm passing in a view model that works with the CheckBoxListFor property and I would like to hide the checkbox section if when I repost to the page there are no check marks ticked. I can show and hide the check box section with no problem using:
我正在传递一个与 CheckBoxListFor 属性一起使用的视图模型，如果我重新发布到页面时没有勾选复选标记，我想隐藏复选框部分。我可以使用以下方法毫无问题地显示和隐藏复选框部分：
$('div.KSearch').hide();
or
或者
$('div.KSearch').show();
What I've been trying to do is check the view model which has a List which hold the information for the keyword model. Is there anyway to check if this list has element being passed in within jquery so that I can show or hide the section with something like:
我一直在尝试做的是检查视图模型，它有一个包含关键字模型信息的列表。无论如何要检查此列表是否在 jquery 中传入了元素，以便我可以使用以下内容显示或隐藏该部分：
if (('@Model.SelectedKeywords').length) {
$('div.KSearch').show();
} else {
$('div.KSearch').hide();
}
but this always shows the section. Any ideas?
但这总是显示该部分。有任何想法吗？
回答by I.G. Pascual
Something like this?
像这样的东西？
var len = @Model.SelectedKeywords.Count;
if (len > 0) {
$('div.KSearch').show();
} else {
$('div.KSearch').hide();
}
('@Model.SelectedKeywords').lengthis treated as a string length in javascript, and it's always positive (and true) ;)
('@Model.SelectedKeywords').length在 javascript 中被视为字符串长度，并且它始终为正数（并且为真）；)
回答by vishpatel73
Check MVC Model is null or not in jquery
在jquery中检查MVC模型是否为空
<script type="text/javascript">
var checkBoxCount = @(Model.SelectedKeywords != null ? Model.SelectedKeywords.Count : 0);
if (checkBoxCount != 0) {
$('div.KSearch').show();
} else {
$('div.KSearch').hide();
}
</script>
I hope this will help.
我希望这将有所帮助。
