javascript - getElementsByTagName does not seem to work -


can please explain why code not working !!

when element id works fine. same method getelementsbytagname() not.

also if use queryselector(), works. if use queryselectorall() same error returns.

test.html:15 uncaught typeerror: cannot set property 'color' of undefined

here code:

<doctype! html> <html> <head>  </head>  <body> <h1>hello world</h1> <p id="par">hello world</p>  <script> var par = document.getelementbyid('par'); par.style.color = "red" var heading = document.getelementsbytagname("h1"); heading.style.color = "red" </script>   </body> </html>

enter image description here

as can see document,getelementsbytagname returns array of elements, not single element.

so have follow proper indexing otherwise throw exception in case.


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