Is header('Content-Type:text/plain'); necessary at all?

php http-headers content-type head response-headers
omg picture omg · Sep 12, 2009 · Viewed 264.7k times · Source

I didn't see any difference with or without this head information yet.

Answer

Jeremy Logan picture Jeremy Logan · Sep 12, 2009

Define "necessary".

It is necessary if you want the browser to know what the type of the file is. PHP automatically sets the Content-Type header to text/html if you don't override it so your browser is treating it as an HTML file that doesn't contain any HTML. If your output contained any HTML you'd see very different outcomes. If you were to send:

<b><i>test</i></b>

a Content-Type: text/html would output:

test

whereas Content-Type: text/plain would output:

<b><i>test</i></b>

TLDR Version: If you really are only outputing text then it doesn't really matter, but it IS wrong.

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