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Preface
I encountered a requirement at work a few days ago. When the user clicks a certain button, a post request is initiated to me in the background, and I accept the passed data. At first, my colleague sent it using the
http_request()
method encapsulated publicly in the company framework. The code is as follows:
public function http_request( $url, $post = '', $timeout = 5 ){ if( empty( $url ) ){ return ; } $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_HEADER, 0); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE); if( $post != '' && !empty( $post ) ){ curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $post); curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json', 'Content-Length: ' . strlen($post))); } curl_setopt($ch, CURLOPT_TIMEOUT, $timeout); $result = curl_exec($ch); curl_close($ch); return $result; }
At first, I didn’t notice that the data passed was
application/json.
Encoded json string, I directly use the data method that accepts the
application/x-www-form-urlencoded
encoding format to get the passed data in the background (that is, directly using the
$_POST
method), Of course, nothing was obtained. Later, my colleague directly changed the
http_request()
method and directly passed the data in the
application/x-www-form-urlencoded
encoding format. I did not make any changes.
Regarding the above question, I have always wondered why I didn’t get the data passed at that time.
The project is basically completed today, and the following has been studied. When the
curl()
makes a post request, the format of the data can be passed in the following ways:
(1): Spliced by parameters The resulting
key=>value
key-value pair string. The format is as follows:
name=xxx&age=23$sex=1
This request parameter is encoded according to
application/x-www-form-urlencoded
by default.
(2): An array of
key=>value
key-value pairs composed of parameters (can only be a one-dimensional array, higher-dimensional arrays will report an error).
The format is as follows:
[ name="xxx" , age = 23 , sex = 男 ]
This request parameter is encoded according to the
multipart/form-data
format by default.
As mentioned above,
curl()
When making a post request, only one-dimensional arrays can be passed as parameters. So what should be done if you want to pass multi-dimensional arrays?
There are two ways to deal with it, namely method 3 and method 4 below.
(3): Process the multi-dimensional array
http_build_query()
and wait for a string in key=>value key-value pair format.
As shown below:
$data = [ "msg"=>"这是一条测试数据", "xxx" => "yyyy", "msg_data" => [ "name"=>"sunms", "age"=>23, "sex"=>"男", "content"=>[ 1,2,3 ] ], ];
will get the following string:
msg=这是一条测试数据&xxx=yyyy&msg_data[name]=sunms&msg_data[age]=23&msg_data[sex]=男&msg_data[content][0]=1&msg_data[content][1]=2&msg_data[content][2]=3
This method is also encoded through the
application/x-www-form-urlencoded进
line, and can be obtained directly through $_POST on the receiving side.
(4): Convert the multi-dimensional array into a string in json format, encode the string in
application/json
format, and pass
file_get_contents(“php://input”)
or
on the receiving side$GLOBALS[‘HTTP_RAW_POST_DATA']
method to obtain the passed json format string, and then convert the json format string into an array for processing.
$data = []; $data_string = json_encode($data); ..... //设置header信息 curl_setopt($ch, CURLOPT_HTTPHEADER, array( 'Content-Type: application/json', 'Content-Length: ' . strlen($data_string)) );
Note: For data encoded in the
application/json
format,
$_POST
cannot be obtained directly. It needs to be obtained through
file_get_contents(“php://input”)
or
$GLOBALS[‘HTTP_RAW_POST_DATA']
.
Summary
The above is a detailed explanation of the precautions for using the curl function to send Post requests in PHP. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!
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