Обзор знаний, связанных с загрузкой файлов PHP

php
date_default_timezone_set('PRC');
if(isset($_POST['submit'])) {
    echo "
";
    var_dump($_FILES['file']);
    echo "
";

    // Method 1 for obtaining file suffix names:
    // Divide file names into arrays with "." as a boundary
    // For an array, the end function takes the last element in the array.
    $ext = end(explode(".", $_FILES['file']['name']));

    // Method 2 for obtaining file suffix names:
    // Find the location of the point in the file name and intercept the string after that location
    //$extpos = strrpos($_FILES['file']['name'],'.');
    //$ext = substr($_FILES['file']['name'], $extpos+1);
    // echo: "File suffix is:" $ext;

    // Setting Uploadable File Types
    $allowType = [
        "gif", "jpeg", "jpg", "png"
    ];
    // Check if uploaded files are supported
    if (!in_array($ext, $allowType)) {
        Die ("please choose the correct file format to upload");
    } else {
        // Name upload file as year, month, day, time, second
        $filename = date("YmdHis", time()) . ".".$ext;
        // Name the upload folder year-month-day and save the files uploaded on the same day
        $directory = "uploads"."/".date("Y-m-d", time());
        // Detecting the existence of the target file directory
        if (!is_dir($directory)) {
            // Create folders if they do not exist
            mkdir ($directory,0777,true);
            // Save temporary files to the same day directory
            move_uploaded_file($_FILES['file']['tmp_name'], $directory . "/" . $filename);
        } else {
            // Detecting whether the file already exists in the target folder
            if (!file_exists()) {
                // Save temporary files to a specified directory if they do not exist
                move_uploaded_file($_FILES['file']['tmp_name'], $directory . "/" . $filename);
            }else{
                Die ("This file already exists");
            }
        }
    }
}
?>




    
    < title > file upload job 
    



    

        

            
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