这是对我有用的jQuery解决方案。clientWidth等没有工作。

function is_overflowing(element, extra_width) {
    return element.position().left + element.width() + extra_width > element.parent().width();
}

如果这不起作用，请确保元素的父元素具有所需的宽度(就个人而言，我必须使用parent().parent())。位置相对于父节点。我还包含了extra_width，因为我的元素(“标签”)包含的图像需要很短的时间来加载，但在函数调用期间，它们的宽度为零，破坏了计算。为了解决这个问题，我使用下面的调用代码:

var extra_width = 0;
$(".tag:visible").each(function() {
    if (!$(this).find("img:visible").width()) {
        // tag image might not be visible at this point,
        // so we add its future width to the overflow calculation
        // the goal is to hide tags that do not fit one line
        extra_width += 28;
    }
    if (is_overflowing($(this), extra_width)) {
        $(this).hide();
    }
});

希望这能有所帮助。

元素可以垂直、水平或同时进行溢出。如果DOM元素被覆盖，这个函数将返回一个布尔值:

function isOverflown(element) {
  return element.scrollHeight > element.clientHeight || element.scrollWidth > element.clientWidth;
}

function isOverflown(element) { return element.scrollHeight > element.clientHeight || element.scrollWidth > element.clientWidth; } var els = document.getElementsByClassName('demos'); for (var i = 0; i < els.length; i++) { var el = els[i]; el.style.borderColor = (isOverflown(el) ? 'red' : 'green'); console.log("Element #" + i + " is " + (isOverflown(el) ? '' : 'not ') + "overflown."); } .demos { white-space: nowrap; overflow: hidden; width: 120px; border: 3px solid black; } <div class='demos'>This is some text inside the div which we are testing</div> <div class='demos'>This is text.</div>

ES6例子:

const isOverflown = ({ clientWidth, clientHeight, scrollWidth, scrollHeight }) => {
    return scrollHeight > clientHeight || scrollWidth > clientWidth;
}

你应该考虑的另一个问题是JS不可用。考虑渐进增强或优雅降级。我建议:

默认添加“更多按钮” 默认添加溢出规则 隐藏按钮，并在JS中进行CSS修改后比较元素。scrollHeight到element.clientHeight

我做了一个多部分的代码依赖演示上述答案(例如使用溢出隐藏和高度)，以及如何展开/折叠溢出项

例1:https://codepen.io/Kagerjay/pen/rraKLB(真正简单的例子，没有javascript，只是剪辑溢出项)

示例2:https://codepen.io/Kagerjay/pen/LBErJL(单个事件处理程序在溢出项上显示更多/无显示)

例3:https://codepen.io/Kagerjay/pen/MBYBoJ(多事件处理程序对溢出项显示更多/显示更少)

我在下面附上了例子3，我使用Jade/Pug，所以它可能有点啰嗦。我建议检查一下我已经使其更容易掌握的相互依赖。

// Overflow boolean checker function isOverflown(element){ return element.scrollHeight > element.clientHeight || element.scrollWidth > element.clientWidth; } // Jquery Toggle Text Plugin $.fn.toggleText = function(t1, t2){ if (this.text() == t1) this.text(t2); else this.text(t1); return this; }; // Toggle Overflow function toggleOverflow(e){ e.target.parentElement.classList.toggle("grid-parent--showall"); $(e.target).toggleText("Show More", "Show LESS"); } // Where stuff happens var parents = document.querySelectorAll(".grid-parent"); parents.forEach(parent => { if(isOverflown(parent)){ parent.lastElementChild.classList.add("btn-show"); parent.lastElementChild.addEventListener('click', toggleOverflow); } }) body { background-color: #EEF0ED; margin-bottom: 300px; } .grid-parent { margin: 20px; width: 250px; background-color: lightgrey; display: flex; flex-wrap: wrap; overflow: hidden; max-height: 100px; position: relative; } .grid-parent--showall { max-height: none; } .grid-item { background-color: blue; width: 50px; height: 50px; box-sizing: border-box; border: 1px solid red; } .grid-item:nth-of-type(even) { background-color: lightblue; } .btn-expand { display: none; z-index: 3; position: absolute; right: 0px; bottom: 0px; padding: 3px; background-color: red; color: white; } .btn-show { display: block; } <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <section> <p>Any grid-parent over 10 child items has a "SHOW MORE" button to expand</p> <p>Click "SHOW MORE" to see the results</p> </section> <radio></radio> <div class="wrapper"> <h3>5 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> <h3>8 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> <h3>10 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> <h3>13 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> <h3>16 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> <h3>19 child elements</h3> <div class="grid-parent"> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="grid-item"></div> <div class="btn-expand">Show More</div> </div> </div>

setTimeout(function(){
    isOverflowed(element)           
},500)

function isOverflowed(element){
    return element.scrollHeight > element.clientHeight || element.scrollWidth > element.clientWidth;
}

这对我来说很管用。谢谢你！

像http://jsfiddle.net/Skooljester/jWRRA/1/这样的代码有用吗?它只是检查内容的高度，并将其与容器的高度进行比较。如果大于，则可以在代码中添加“显示更多”按钮。

更新:增加了在容器顶部创建“Show More”按钮的代码。