Understanding HTTP Response Status Codes

What Are HTTP Response Status Codes?

Hypertext Transfer Protocol (HTTP) response status codes  are numeric values that get issued by servers in response to requests that have been sent to the server. Most developers will be familiar with the phrase '404 Error'.  The '404' in this instance refers to the HTTP response status code that usually gets issued by a server whenever a page is not found.  Other well known response codes included '200' which is the status of a webpage (or endpoint) that has successfully loaded, and also '301' which indicates when a webpage has moved permanently.  These are just a few of the HTTP Response Status Codes that are available.  There are, however, lots of HTTP Response Status Codes - with more are being added all the time!

How To Fetch HTTP Response Status Codes In PHP

In PHP, you can fetch the HTTP Response Status Code by using PHP's inbuilt http_response_code() function.  For example,

$status = http_response_code();
echo $status; //outputs (something like) 200

How To Set HTTP Response Status Codes In PHP

In PHP, you set the HTTP Response Status Code (for a webpage or an API endpoint) by invoking http_response_code() and passing in a numeric value - that represents the HTTP Response Status Code - into the method.  For example,

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http_response_code(422);
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HTTP Response Status Codes Reference