javascript - How to get element by class name? -


this question has answer here:

using javascript, can element id using following syntax:

var x=document.getelementbyid("by_id");

i tried following element class:

var y=document.getelementbyclass("by_class");

but resulted error: 

getelementbyclass not function

how can element class?

the name of dom function getelementsbyclassname, not getelementbyclassname, because more 1 element on page can have same class, hence: elements.

the return value of nodelist instance, or superset of nodelist (ff, instance returns instance of htmlcollection). @ rate: return value array-like object:

var y = document.getelementsbyclassname('foo'); var anode = y[0];

if, reason need return object array, can easily, because of magic length property:

var arrfromlist = array.prototype.slice.call(y); //or per antonb's comment: var arrfromlist = [].slice.call(y);

as yckart suggested queryselector('.foo') , queryselectorall('.foo') preferable, though, are, indeed, better supported (93.99% vs 87.24%), according caniuse.com:


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