PHP文件上传和覆盖同名文件

Question

我正在制作一个应用程序，允许用户通过 PHP 上传目录中的文件。

我遇到了问题，因为它不允许我覆盖具有相同名称的文件。 例如，我有一个名为 text.php 的文件并上传了它，现在当我返回并更改文件 text.php 的内容并再次将其上传到服务器时，我仍然拥有未经编辑的版本。但是，如果我上传另一个文件，它就可以工作。所以我不能覆盖文件。

if ($_POST["greg"]=='true'){
// Set local PHP vars from the POST vars sent from our form using the array
// of data that the $_FILES global variable contains for this uploaded file
$fileName = $_FILES["file1"]["name"]; // The file name
$fileTmpLoc = $_FILES["file1"]["tmp_name"]; // File in the PHP tmp folder
$fileType = $_FILES["file1"]["type"]; // The type of file it is
$fileSize = $_FILES["file1"]["size"]; // File size in bytes
$fileErrorMsg = $_FILES["file1"]["error"]; // 0 for false... and 1 for true

// Specific Error Handling if you need to run error checking
if (!$fileTmpLoc) { // if file not chosen
    echo "ERROR: Please browse for a file before clicking the upload button.";
    exit();
} else if($fileSize > 90000000000000) { // if file is larger than we want to allow
    echo "ERROR: Your file was larger than 50kb in file size.";
    unlink($fileTmpLoc);
    exit();
} else if (!preg_match("/.(doc|docx|xls)$/i", $fileName) ) {
     // This condition is only if you wish to allow uploading of specific file types    
     echo "ERROR: Your file is not the right format contact the master of the page for clarification.";
     unlink($fileTmpLoc);
     exit();
}
// Place it into your "uploads" folder mow using the move_uploaded_file() function
move_uploaded_file($fileTmpLoc, "documenti/$fileName");
// Check to make sure the uploaded file is in place where you want it
if (!file_exists("documenti/$fileName")) {
    echo "ERROR: File not uploaded<br /><br />";
    echo "Check folder permissions on the target uploads folder is 0755 or looser.<br /><br />";
    echo "Check that your php.ini settings are set to allow over 2 MB files, they are 2MB by default.";
    exit();
}
// Display things to the page so you can see what is happening for testing purposes
echo "The file named <strong>$fileName</strong> uploaded successfuly.<br /><br />";
echo "It is <strong>$fileSize</strong> bytes in size.<br /><br />";
echo "It is a <strong>$fileType</strong> type of file.<br /><br />";
echo "The Error Message output for this upload is: <br />$fileErrorMsg";

}

如何更改此代码，以便在我上传同名文件时覆盖现有文件？

Answer 1

试试这个(在上传文件之前把它)

//checking if file exsists
if(file_exists("documenti/$fileName")) unlink("documenti/$fileName");

//Place it into your "uploads" folder mow using the move_uploaded_file() function
move_uploaded_file($fileTmpLoc, "documenti/$fileName");