我如何在这个上传脚本中构建uniqid函数？
我的目标是将图片上传到服务器，并将图片重命名为随机字符，然后在图片上传后，将图片链接回显。
所以这就是我想象的方式： 上传image.png＆gt; script processes image.png并使用uniqid函数给它一个随机名称，如3ia8d3awd.png＆gt; 然后脚本回显新图像名称，并在图像上传到目录后将其链接到标记中。
这是脚本：
<?php
$target_dir = "..img/";
$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);
$uploadOk = 1;
$imageFileType = pathinfo($target_file,PATHINFO_EXTENSION);
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) {
$check = getimagesize($_FILES["fileToUpload"]["tmp_name"]);
if($check !== false) {
echo "File is an image - " . $check["mime"] . ".";
$uploadOk = 1;
} else {
echo "File is not an image.";
$uploadOk = 0;
}
}
// Check if file already exists
if (file_exists($target_file)) {
echo "Sorry, file already exists.";
$uploadOk = 0;
}
// Check file size
if ($_FILES["fileToUpload"]["size"] > 500000) {
echo "Sorry, your file is too large.";
$uploadOk = 0;
}
// Allow certain file formats
if($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType !=
"jpeg"
&& $imageFileType != "gif" ) {
echo "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
$uploadOk = 0;
}
// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0) {
echo "Sorry, your file was not uploaded.";
// if everything is ok, try to upload file
} else {
if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"],
$target_file)) {
echo "The file ". basename( $_FILES["fileToUpload"]["name"]). " has
been uploaded.";
} else {
echo "Sorry, there was an error uploading your file.";
}
}
?>
我知道这个脚本是为了按原样拍摄图像名称并上传它们，但如果你能帮我修改一下。我认为这将是unqid功能，但我可能是错的。我还是PHP新手，花了两个小时试图弄清楚这个;谢谢。
编辑：被告知more_entropy函数将提供更多唯一名称。
答案 0 :(得分：0)
在代码顶部试试这个：
$newFileName = uniqueid('',TRUE);
$_FILES["fileToUpload"]["name"] = $newFileName;
这应该为文件指定一个新的唯一名称。当然，我没有测试它是否会干扰文件扩展名，但让我知道它是如何工作的。
答案 1 :(得分：0)
这是修改过的脚本，只是插入了用户定义的函数来生成随机且最可能唯一的名称，有4个名称段，每个段长度为6个字符，您可以在函数uniqueName中自定义这些设置
<?php
function genName($length = 10) {
$characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$charactersLength = strlen($characters);
$randomString = '';
for ($i = 0; $i < $length; $i++) {
$randomString .= $characters[rand(0, $charactersLength - 1)];
}
return $randomString;
}
function uniqueName()
{
$temp = '';
for($i = 0;$i<4;$i++) //number of random segments
$temp .= '_'.genName(6); // length of each segment
return $temp;
}
$_FILES["fileToUpload"]["name"] = uniqueName();
$target_dir = "..img/";
$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);
$uploadOk = 1;
$imageFileType = pathinfo($target_file,PATHINFO_EXTENSION);
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) {
$check = getimagesize($_FILES["fileToUpload"]["tmp_name"]);
if($check !== false) {
echo "File is an image - " . $check["mime"] . ".";
$uploadOk = 1;
} else {
echo "File is not an image.";
$uploadOk = 0;
}
}
// Check if file already exists
if (file_exists($target_file)) {
echo "Sorry, file already exists.";
$uploadOk = 0;
}
// Check file size
if ($_FILES["fileToUpload"]["size"] > 500000) {
echo "Sorry, your file is too large.";
$uploadOk = 0;
}
// Allow certain file formats
if($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType !=
"jpeg"
&& $imageFileType != "gif" ) {
echo "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
$uploadOk = 0;
}
// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0) {
echo "Sorry, your file was not uploaded.";
// if everything is ok, try to upload file
} else {
if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"],
$target_file)) {
echo "The file ". basename( $_FILES["fileToUpload"]["name"]). " has
been uploaded.";
} else {
echo "Sorry, there was an error uploading your file.";
}
}
?>
答案 2 :(得分：0)
原始版本的经过修改和未经测试的版本，具有较小的实用程序功能，可帮助为上传的文件生成随机（并且希望是唯一的）名称。
<?php
if( $_SERVER['REQUEST_METHOD']=='POST' && !empty( $_FILES ) ){
/*
generate a random name for new files
*/
function createname( $prefix='',$name, $length=16 ){
/* random chars with optional prefix & length */
return $prefix.substr( sha1( $name . uniqid( $prefix, true ) . time() ), 0, $length );
}
try{
/* Only permit these file extensions */
$allowed=array('jpg','jpeg','png','gif');
/* Do not allow files larger than this */
$maxsize=500000;
/* optional prefix to generated file name - can be '' */
$prefix='img_';
$target_dir = "..img/";
/* Get reference to file as object for convenience */
$file=(object)$_FILES['fileToUpload'];
$name=$file->name;
$size=$file->size;
$tmp=$file->tmp_name;
$type=$file->type;
$error=$file->error;
/* File extension */
$ext=pathinfo( $name, PATHINFO_EXTENSION );
$filename=pathinfo( $name, PATHINFO_FILENAME );
/* target will be similar to "..img/img_a7119f62b2810c68.jpg" */
$targetfile=createname( $prefix, $filename ) . '.' . $ext;
$targetpath=$target_dir . $targetfile;
if( $error==UPLOAD_ERR_OK && is_uploaded_file( $tmp ) ){
/* Is the file an image? */
list( $w, $h, $t, $a ) = getimagesize( $tmp );
if( !$w or !$h ) throw new Exception('File is not an image');
/* Correct file extension? */
if( !in_array( $ext, $allowed ) ) throw new Exception('Incorrect file extension - only '.implode(', ',$allowed).' are permitted');
/* Does file already exist ( unlikely if using unique random names ) */
if( realpath( $targetpath ) ) throw nex Exception('File already exists');
/* Is file too large? */
if( $size > $maxsize )throw new Exception('File is too large');
/* save the file */
$status=move_uploaded_file( $tmp, $targetpath );
echo $status ? "The file has been saved: <a href='$targetpath' target='_blank'>{$targetfile}</a>" : "Sorry - there was a problem saving the file. Check permissions on folder.";
} else {
throw new Exception('upload failed');
}
}catch( Exception $e ){
exit( $e->getMessage() );
}
}
?>