javascript检查链接中的文本锚文本是否溢出

Question

当我拥有这个css/html时，是否可以检查锚文本是否溢出？

<a href="#" style"overflow:hidden; width:100px; display:block;> 
    This is a very long text. This is a very long text. This is a very long text. 
</a> 

使用jQuery或纯JavaScript

Answer 1

您可以将文本内容到TMP元素，然后计算其宽度与<a>宽度进行比较，以检查内容溢出与否。见下文，

DEMO

$('a').on('click', function() { 
    var $tmp = $('<a/>') 
       .text($(this).text()) 
       .css('display','none') 
       .appendTo('body'); 
    alert(($tmp.width() > $(this).width())?'Overflows':'Perfectly Inside'); 
    $tmp.remove(); 
}); 

Answer 2

我建议：

var as = document.getElementsByTagName('a'); 

for (var i=0,len=as.length;i<len;i++){ 
    var that = as[i] 
     w = that.offsetWidth, 
     w2 = that.scrollWidth; 
    if (w<w2) { 
     console.log("This content overran!"); 
    } 
}​ 

JS Fiddle demo。

---

差不多以上，但下面还增加了一个 '报告' 元素的DOM：

var as = document.getElementsByTagName('a'); 

for (var i=0,len=as.length;i<len;i++){ 
    var that = as[i], 
     w = that.offsetWidth, 
     w2 = that.scrollWidth, 
     s = document.createElement('span'); 
    if (w<w2) { 
     var text = document.createTextNode('This content overran the container, a, element by ' + (w2-w) + 'px.'); 
     s.appendChild(text); 
     that.parentNode.insertBefore(s,that.nextSibling); 
    } 
}​ 

JS Fiddle demo。

Answer 3

试试这个

<div id="parent" style="overflow:hidden; width:100px;display:block"> 
<a id="textblock" href="#" style="white-space: nowrap;" > 
    This 
</a> 
</div> 
<script> 
    var p=document.getElementById("parent"); 
    var tb=document.getElementById("textblock"); 
    (p.offsetWidth<tb.offsetWidth)?alert('long'):alert('short'); 
</script>​ 

Answer 4

HTML：

<a id="a1" href="#" style="overflow:hidden; width:100px; height:10px; display:block"> 
    This is a very long text. This is a very long text. This is a very long text. 
</a> 
<a id="a2" href="#" style="width:100px; height:10px; display:block"> 
    This is a very long text. This is a very long text. This is a very long text. 
</a> 

JS：

function hasOverflow($el){ 
    return $el.css("overflow")==="hidden" && 
      ($el.prop("clientWidth") < $el.prop("scrollWidth") || 
      $el.prop("clientHeight") < $el.prop("scrollHeight")); 
} 
console.log(hasOverflow($("#a1")));  //true 
console.log(hasOverflow($("#a2")));  //false 

DEMO