我想在客户端检查在提交表单之前是否已选择文件.
<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script> <script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script> @using (Html.BeginForm("Upload","Files",FormMethod.Post,new { enctype = "multipart/form-data" })) { <input id="File" name="File" type="file" size="80" /> <input type="submit" name="name" value="Upload" /> }
目前,此表单正在进行回发以进行验证.出了什么问题?