SoFunction
Updated on 2025-03-09

PHP upload function set suffix name judgment and random naming (strongly recommended)

No more nonsense, please see the code example below for details.

<html>
<head>
  <meta http-equiv="content-type" content="text/html" charset="utf-8">
  <title>Upload Image</title>
</head>
<body>
<form method="post" action="" enctype="multipart/form-data">
  <input type="hidden" name="MAX_FILE_SEZE" value="2000000">
  <input type="file" name="file" value="view">
  <input type="submit" value="upload" name="B1">
</form>
</body>
</html>

&lt;?php
include(""); //Introduce custom function files$type = array("jpg", "gif", "bmp", "jpeg", "png");
// Determine the uploaded file type$fileext = strtolower(fileext($_FILES['file']['name']));
$uploadfilename = random(8);
if(in_array($fileext, $type)){
  $filename = explode(".", $_FILES['file']['name']);

    if(is_uploaded_file($_FILES['file']['tmp_name'])){
//    echo $_FILES['file']['tmp_name'];
    $flag = move_uploaded_file($_FILES['file']['tmp_name'], "/Library/WebServer/Documents/test/".$uploadfilename.".".$fileext);
    if($flag){
      echo "Uploaded successfully!";
    }else{
      echo "Error.";
    }
    echo "&lt;a href='javascript:(-1)'&gt;Back&lt;/a&gt;";
  }
}

&lt;?php
header("Content-type:text/html;charset=utf8");
// Get the file suffix name functionfunction fileext($filename){
  $sTemp = strrchr($filename, ".");
  return substr($sTemp, 1);
}
function fileext2($filename){
  $sTemp = explode(".", $filename);
  return $sTemp[count($sTemp)-1];
}
// Generate random filename functionfunction random($length){
  $captchaSource = "0123456789abcdefghijklmnopqrstuvwxyz This is an example of random printout strings";
  $captchaResult = "2015"; // Random number returns value  $captchaSentry = ""; // Intermediate variable of random number  for($i=0;$i&lt;$length;$i++){
    $n = rand(0, 35); #strlen($captchaSource));
    if($n &gt;= 36){
      $n = 36 + ceil(($n-36)/3) * 3;
      $captchaResult .= substr($captchaSource, $n, 3);
    }else{
      $captchaResult .= substr($captchaSource, $n, 1);
    }
  }
  return $captchaResult;
}
?&gt;

Consolidate three files into one:

&lt;?php
// Get the file suffix name functionfunction fileext($filename){
  $sTemp = strrchr($filename, ".");
  return substr($sTemp, 1);
}
function fileext2($filename){
  $sTemp = explode(".", $filename);
  return $sTemp[count($sTemp)-1];
}
// Generate random filename functionfunction random($length){
  $captchaSource = "0123456789abcdefghijklmnopqrstuvwxyz This is an example of random printout strings";
  $captchaResult = "2015"; // Random number returns value  $captchaSentry = ""; // Intermediate variable of random number  for($i=0;$i&lt;$length;$i++){
    $n = rand(0, 35); #strlen($captchaSource));
    if($n &gt;= 36){
      $n = 36 + ceil(($n-36)/3) * 3;
      $captchaResult .= substr($captchaSource, $n, 3);
    }else{
      $captchaResult .= substr($captchaSource, $n, 1);
    }
  }
  return $captchaResult;
}
$type = array("jpg", "gif", "bmp", "jpeg", "png");
// Determine the uploaded file type$fileext = strtolower(fileext($_FILES['file']['name']));
$uploadfilename = random(8);
if(in_array($fileext, $type)){
  $filename = explode(".", $_FILES['file']['name']);
  if(is_uploaded_file($_FILES['file']['tmp_name'])){
//    echo $_FILES['file']['tmp_name'];
    $flag = move_uploaded_file($_FILES['file']['tmp_name'], "/Library/WebServer/Documents/test/".$uploadfilename.".".$fileext);
    if($flag){
      echo "Uploaded successfully!";
    }else{
      echo "Error.";
    }
    echo "&lt;a href='javascript:(-1)'&gt;Back&lt;/a&gt;";
  }
}
?&gt;
&lt;html&gt;
&lt;head&gt;
  &lt;meta http-equiv="content-type" content="text/html" charset="utf-8"&gt;
  &lt;title&gt;Upload Image&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
&lt;form method="post" action="" enctype="multipart/form-data"&gt;
  &lt;input type="hidden" name="MAX_FILE_SEZE" value="2000000"&gt;
  &lt;input type="file" name="file" value="view"&gt;
  &lt;input type="submit" value="upload" name="B1"&gt;
&lt;/form&gt;
&lt;/body&gt;
&lt;/html&gt;

The above content is the suffix name judgment and random naming of the php upload function set that you explained (strongly recommended). I hope you like it.