PHP implements the function of uploading files through CURL

This article mainly introduces the function of uploading files through CURL in PHP, and analyzes the related attribute settings and usage skills of PHP using curl file upload operation in the form of examples. Friends in need can refer to the following

The examples of this article are described Use PHP to implement the function of uploading files through CURL. Share it with everyone for your reference. The details are as follows:

PHP uses CURL to upload files. Just send a POST request. Set a certain field in the request to the full path of the file that needs to be uploaded, and start with "@ ", and then use CURL to send the variable to the server in POST mode. The corresponding uploaded file information can be obtained from the super global variable $_FILES on the server side.

Below we use an example to show this process.

Assume that there is a text file log.txt locally, its path is "/www/test/log.txt", and the content is as follows:

this is a file for test
hello PythonTab!

In order to upload this file to the server-side script http://www.php.cn/article.html, we wrote a local script named curl_file.php with the following content:

## The logic of #

<?php
$url = "http://www.php.cn/article.html";
$post_data = array(
"foo" => "bar",
//要上传的本地文件地址
"upload" = > "@/www/test/log.txt"
);
$ch = curl_init();
curl_setopt($ch , CURLOPT_URL , $url);
curl_setopt($ch , CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch , CURLOPT_POST, 1);
curl_setopt($ch , CURLOPT_POSTFIELDS, $post_data);
$output = curl_exec($ch);
curl_close($ch);
echo $output;
?>

curl_file.php is very simple. Set the POST variable

$post_data, where upload points to the file that needs to be sent. It should be noted here that when we used POST before, we sent a string, and then used file_get_contents("php//input") on the server side to get the string. The usage here is different. In fact, POST You can also send key-value pairs like GET. There is a super global variable $_POST on the server side that can obtain the value of the corresponding POST data just like $_GET. It should be noted that the variable for uploading files does not exist in $_POST, but in $_FILES.

In order to show the logic of the server receiving the file upload request from the above code, we wrote the following code in upload.php:

<?php
echo var_export($_FILES,true);
echo file_get_contents($_FILES[&#39;upload&#39;][&#39;tmp_name&#39;]);
copy($_FILES[&#39;upload&#39;][&#39;tmp_name&#39;], "./log_copy.txt");
?>

upload.php first uses

var_export to output the $_FILES variable to standard output, and then uses file_get_contents to read $_FILES['upload'][ 'tmp_name'] and output the contents of the file to standard output, and then copy the file named $_FILES['upload']['tmp_name'] to log_copy.txt in the current directory. in the file. The standard output of the script is as follows:

array(
'upload' =>
array(
'name' => 'log.txt',
'type' => 'application/octet-stream',
'tmp_name' => '/tmp/phpLUB59F',
'error' => 0,
'size' => 36,
)
)
this is a file for test
hello PythonTab!

You can see that there is an upload array in the $_FILES variable, which corresponds to the uploaded file description information, where name and type represent the name and type respectively. tmp_name is more critical. After the server receives the uploaded file, it will write the file in a temporary file. The name of this temporary file is the value of tmp_name. This is why we can get the file contents of a log.txt by reading the file. . Generally, after the server receives the uploaded file, it needs to read the file immediately or copy the file to another file, because the temporary file pointed to by tmp_name will be deleted after the server script is executed. The upload.php script The last line is to copy the temporary file to our target file.

Related recommendations:

php method of calling .Net's WebService asmx file through soap

PHP method of calling .Net's WebService asmx file through strace Methods to locate the cause of the fault

The above is the detailed content of PHP implements the function of uploading files through CURL. For more information, please follow other related articles on the PHP Chinese website!