Spring MVC - 为什么我在 GET 请求中需要模型对象？
看一下 Spring 提供的用于处理表单提交的示例： https://github.com/spring-guides/gs-handling-form-submission/tree/main/complete 这是 Spring MVC 控件的基本示例...
这是小提琴（对警报感到抱歉）http://jsfiddle.net/PCcqJ/92/ var ractive = new Ractive({ 模板：'#templateOne'， 部分：{ aPartial：'哦，看，partia... 这是小提琴（抱歉有警报）http://jsfiddle.net/PCcqJ/92/ var ractive = new Ractive({ template: '#templateOne', partials: { aPartial: '<div>Oh look, the partial is rendered!</div>' } }); function cb() { alert('but now we unrender'); ractive.once('complete', function() { alert('we rendered again, and now you can\'t see the partial content'); }); ractive.render('container'); } ractive.render('container'); ractive.once('complete', function() { alert('so we render the first time, and you can see the partial'); ractive.unrender().then(cb); }); 此处的部分不会重新渲染。为什么是这样？部分仍在部分对象中，并且它们尚未渲染，那么什么会阻止它们再次渲染？ 这个小提琴会渲染、取消渲染，然后重新渲染，每次发生其中一种情况时都会向您发出警报。 我做了一个工作jsfiddle：https://jsfiddle.net/43gLqbku/1/ <div id='container'></div> <script id="templateOne" type="x-template"> {{>aPartial}} </script> var ractive = new Ractive({ el:"#container", template: '#templateOne', partials: { aPartial: '<div>Oh look, the partial is rendered!</div>' } }); function cb() { alert('but now we unrender'); ractive.once('complete', function() { alert('we rendered again, and now you can\'t see the partial content'); }); ractive.render('container'); } //ractive.partials.part = '<div>this is a partial</div>'; ractive.once('complete', function() { alert('so we render the first time, and you can see the partial'); ractive.unrender().then(cb); }); 在调用render之前需要调用ractive.once('completed') 你不需要 ractive.render("container");在活动代码下，因为它在第一次运行时自动呈现 在你的jsfiddle中你导入的ractive不起作用 你没有在 jsFiddle 活动代码中包含 el:"#container"
引导进度条在我的 MVC 索引视图上不起作用。 我已经用 Chrome 和 Internet Explorer 尝试过了。 @{ ViewBag.Title = "首页"; } 引导进度条在我的 MVC 索引视图上不起作用。 我已经用 Chrome 和 Internet Explorer 尝试过了。 @{ ViewBag.Title = "Home Page"; } <div class="jumbotron"> <h1>ASP.NET</h1> <p class="lead">ASP.NET is a free web framework for building great Web sites and Web applications using HTML, CSS and JavaScript.</p> <p><a href="http://asp.net" class="btn btn-primary btn-large">Learn more »</a></p> </div> <div class="row"> <div class="col-md-4"> <h2>Getting started</h2> <div class="progress-bar progress-striped "></div> </div> </div> 本次聚会迟到了，但在我使用的 Bootstrap 版本（v3.1.1）中，该类是“progress-striped”（不是像文档所说的“progress-bar-striped”），并且它和“active” ' 类必须应用于外部 div: <div class="progress progress-striped active"> <div class="progress-bar" role="progressbar" aria-valuenow="0" aria-valuemin="0" aria-valuemax="100" style="width: 0%;">Some text</div> </div> 查看 CSS，选择器“progress-bar”已更改为“bar”： ./bootstrap.css: .progress { ... } .progress .bar { ... } 因此，将您的代码更改为 <div class="progress"> <div class="bar"> </div> </div> 然后就可以了。 不确定这种疯狂的原因是什么，似乎引导文档还没有更新。 <div class="progress"> <div class="progress-bar progress-bar-striped progress-bar-animated" role="progressbar" aria-valuenow="75" aria-valuemin="0" aria-valuemax="100" style="width: 75%"></div> </div> 这样进度动画就可以工作了。 <div class="progress"> <div class="progress-bar" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria-valuemax="100" style="width: 60%;"> <span class="sr-only">60% Complete</span> </div> </div> 上面是 bootstrap v3.1.1 的代码，看起来你的进度条 div 缺少一些元素？ 如果您使用 Bootstrap v4 并且需要动画，则需要使用 progress-bar-animated 而不是 active。
在 Rails 5 中单击浏览器上的后退按钮时，带有 Select2 的表单会重复
_header.html.erb（用于表单部分） <%= form_for home_path, class: 'home', role: 'search', method: :get do |f| %> _header.html.erb（用于表单部分） <%= form_for home_path, class: 'home', role: 'search', method: :get do |f| %> <div class="form-group" style="display:inline;"> <div class="input-group input-group-md"> <%= text_field_tag :q, params[:q], placeholder: ... ,class: 'form-control hideOverflow', type: "search" %> <%= select_tag "category", options_from_collection_for_select(...),include_blank: true, class: 'form-control hideOverflow', type: "search" %> <%if logged_in? %> <%= select_tag "location", options_for_select([...], ...),class: 'form-control hideOverflow', type: "search" %> <% else %> <%= select_tag "location", options_for_select([...], ...),class: 'form-control hideOverflow', include_blank: true, type: "search" %> <% end %> <span class="input-group-addon"><%= submit_tag "Search", class: "btn-transparent"%></span> </div> </div> <% end %> JS代码 <script> $( document ).on('turbolinks:load', function() { $('select#category').select2({ width: '60%', dropdownAutoWidth : true, placeholder: "Choose a category", maximumSelectionLength: 3 }); $('select#location').select2({ width: '40%', dropdownAutoWidth : true, minimumResultsForSearch: Infinity }); }); </script> 故障或渲染问题（单击链接查看图像） 有人可以帮我解决为什么吗？另外，我的搜索表单位于标题部分文件的导航栏中。 如果我去掉脚本中的 $(...).select ，一切都会正常...我认为 select.js 有问题 在此回复： https://stackoverflow.com/a/41915129/5758027 我在自己的代码中使用了这个解决方案： $(document).on('turbolinks:before-cache', function() { // this approach corrects the select 2 to be duplicated when clicking the back button. $('.select-select2').select2('destroy'); $('.select-search-select2').select2('destroy'); } ); 和观察者： $(document).ready( ready ); //... once document ready $(document).ajaxComplete( ready ); //... once ajax is complete $(document).on('turbolinks:load', ready ); //... once a link is clicked function ready() { $(".select-search-select2").select2({ theme: "bootstrap", language: 'es', allowClear: true }); $(".select-select2").select2({ theme: "bootstrap", language: 'es', minimumResultsForSearch: Infinity, allowClear: true }); }; 总是清除缓存不是会让使用 Turbolink 变得毫无意义吗？ 不如这样？ $(document).on('turbolinks:before-cache', function(e) { return $('.form-control.select2').each(function() { return $(this).select2('destroy'); }); }); 我无法解决这个渲染问题（仍在等待正确的答案！），但如果有人像我一样遇到类似的问题，请尝试跳出框框思考。这是我的技巧：我在应用程序中添加了一个后退按钮。 获取完整的url路径 # get the previous url def save_previous_page session[:return_to] = request.fullpath end 仅当页面不是主页或搜索页面时才显示后退按钮 <% if session[:return_to] != request.fullpath%> <%= link_to session.delete(:return_to) || request.fullpath, class: 'back-button' do%> <i class="fa fa-arrow-circle-left" aria-hidden="true"></i> <%end%> <% end %> 同时，我仍在等待并尝试解决渲染问题... 解决了问题 只需将此代码添加到您的 .js 文件中 Turbolinks.clearCache(); 这很可能是一些资源不一致，您应该检查您的 app\views\layouts 文件夹中是否有重复声明 wither jQuery、jQuery UJS 或 Turbolinks 的文件。检查页面的所有 <script> 标签，以及是否在 layout 文件夹和内部视图中声明相同的脚本。如果情况并非如此，请检查是否有 render、yield 或 build 呼叫 简单的解决方案，不要在您不希望它运行的东西上运行 select2 构建器。 $("select#category:not(.select2-container):not(.select2-hidden-accessible)").select2(); Rails 7 更新 这里的很多东西在 Rails 7 中都不起作用，尤其是 turbolinks:before-cache 事件。您正在寻找的新事件是 turbo:before-cache 和 turbo:load，所以它看起来像这样： $(document).on("turbo:before-cache", function() { $("#select_id").select2('destroy'); }); $(document).on('turbo:load', function() { $('#select_id').select2(); });
我有以下html和css代码： html，正文{ 保证金：0； } #包含...</desc> <question vote="0"> <p>我有以下 html 和 css 代码：</p> <pre><code><!DOCTYPE html> <html> <head> <style type="text/css"> html, body { margin: 0; } #container{ width:100vw; height:100vh; background-color: green; } #left-bar{ position: absolute; width: 300px; height: 100vh; background-color: red; overflow: scroll; } </style> </head> <body> <div id="container"> <div id="left-bar" > </div> </div> </body> </html> </code></pre> <p>它给出： <a href="https://i.sstatic.net/sbXnw.png" rel="nofollow noreferrer"><img src="https://cdn.txt58.com/i/AWkuc3N0YXRpYy5uZXQvc2JYbncucG5n" alt="extra padding overflow scroll"/></a></p> <p>左侧栏内有一个填充，我不明白为什么以及如何删除它。</p> <p>我尝试过的事情：</p> <ul> <li>在左侧栏上添加<pre><code>padding: 0;</code></pre>，它不起作用（也可以使用<pre><code>!important</code></pre>）。</li> <li>使用检查器来了解填充的来源。我没找到。</li> <li>删除左侧栏上的<pre><code>overflow: scroll</code></pre>。它有效，但我希望左栏具有以下行为 <pre><code>overflow: scroll</code></pre></li> </ul> <p><strong>如何删除左栏中的填充？</strong></p> <p><strong>编辑：错误用完全相同的代码消失了。</strong></p> <p>现在使用相同的代码： <a href="https://i.sstatic.net/Ch1IF.png" rel="nofollow noreferrer"><img src="https://cdn.txt58.com/i/AWkuc3N0YXRpYy5uZXQvQ2gxSUYucG5n" alt="no padding"/></a></p> <p>我做了什么：</p> <ul> <li>重启电脑，bug依然存在</li> <li>添加CSS代码来设置滚动条的样式</li> <li>删除我添加的代码 --> bug 消失了</li> </ul> <p>我不明白为什么...</p> </question> <answer tick="false" vote="0"> <p>您看到的是一个空的滚动条。设置溢出<pre><code>overflow: auto</code></pre>。仅当内容溢出时才会显示滚动条。</p> <p></p><div data-babel="false" data-lang="js" data-hide="false" data-console="true"> <div> <pre><code><!DOCTYPE html> <html> <head> <style type="text/css"> html, body { margin: 0; } #container{ width:100vw; height:100vh; background-color: green; } #left-bar{ position: absolute; width: 300px; height: 100vh; background-color: red; overflow: auto; } </style> </head> <body> <div id="container"> <div id="left-bar" > </div> </div> </body> </html></code></pre> </div> </div> <p></p> </answer> <answer tick="false" vote="0"> <p>您可能会考虑使用一个具有最小滚动条的插件（也许是<a href="https://grsmto.github.io/simplebar/" rel="nofollow noreferrer">simplerbar</a>）。还可以考虑只做 <pre><code>overflow-y:scroll</code></pre> 以获得更容易接受的外观。您还可以更改滚动装订线的颜色<a href="https://developer.mozilla.org/en-US/docs/Web/CSS/scrollbar-color" rel="nofollow noreferrer">colors</a></p> <p></p><div data-babel="false" data-lang="js" data-hide="false" data-console="true"> <div> <pre><code>var el1 = document.querySelector('[data-id=div1]'); var el2 = document.querySelector('[data-id=div2]'); instance1 = new SimpleBar(el1); instance2 = new SimpleBar(el2);</code></pre> <pre><code><script src="https://cdnjs.cloudflare.com/ajax/libs/simplebar/5.3.8/simplebar.min.js" integrity="sha512-2SAzoBQi2FbvWkvcsoYW4PH478pUu0gwa7BRA6YQxg6kCWUIOIDfFHMLH57GbWeLa+pkYitOD5j9mIhIt3CLKA==" crossorigin="anonymous" referrerpolicy="no-referrer"></script> <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/simplebar/5.3.8/simplebar.min.css" integrity="sha512-uZTwaYYhJLFXaXYm1jdNiH6JZ1wLCTVnarJza7iZ1OKQmvi6prtk85NMvicoSobylP5K4FCdGEc4vk1AYT8b9Q==" crossorigin="anonymous" referrerpolicy="no-referrer" /> <div dir="ltr"> <div data-id="div1" style="height: 300px; width: 200px; padding:10px; display: inline-block; border:1px solid gray; background: lightblue; "> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p> </div> <section data-id="div2" style="height: 300px; width: 200px; padding:10px; display: inline-block; border:1px solid gray"> <p>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</p> <p>But I must explain to you how all this mistaken idea of denouncing pleasure and praising pain was born and I will give you a complete account of the system, and expound the actual teachings of the great explorer of the truth, the master-builder of human happiness. No one rejects, dislikes, or avoids pleasure itself, because it is pleasure, but because those who do not know how to pursue pleasure rationally encounter consequences that are extremely painful. Nor again is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure. To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it? But who has any right to find fault with a man who chooses to enjoy a pleasure that has no annoying consequences, or one who avoids a pain that produces no resultant pleasure?</p> </section> </div></code></pre> </div> </div> <p></p> </answer> </body></html>