Use PHP built-in functions to quickly develop gadgets

In daily development, we often need to write some small tools to meet our own or team's needs, such as file upload, image compression, character transcoding, etc. These functions can be quickly implemented using PHP built-in functions. This article will introduce how to use PHP built-in functions to quickly develop gadgets.

1. File upload

File upload is one of the common functions in website development. In PHP, you can use the $_FILES and move_uploaded_file functions to implement file upload.

$_FILES is an array containing uploaded file information, including file name, file type, file size, temporary file name, etc. The move_uploaded_file function can move the uploaded file to the specified directory.

The following is a simple file upload example:

<form method="post" enctype="multipart/form-data">
    <input type="file" name="file">
    <input type="submit" value="上传">
</form>
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $upload_dir = "upload/";
    $file_name = $_FILES["file"]["name"];
    $file_tmp = $_FILES["file"]["tmp_name"];
    if(move_uploaded_file($file_tmp, $upload_dir . $file_name)){
        echo "文件上传成功";
    }
    else{
        echo "文件上传失败";
    }
}
?>

2. Image compression

Image compression can reduce the size of image files and improve web page loading speed . In PHP, you can use the GD library to implement image compression.

GD library is an open source drawing library that can generate pictures in various formats. The GD library in PHP provides a wealth of functions and methods, including image compression, cropping, rotation and other functions.

The following is a simple image compression example:

<?php
$src = "image.jpg";
list($width, $height) = getimagesize($src);
$new_width = 100;
$new_height = $height * ($new_width / $width);
$dst = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefromjpeg($src);
imagecopyresampled($dst, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
imagejpeg($dst, "image_compress.jpg");
imagedestroy($dst);
imagedestroy($image);
?>

3. Character transcoding

When processing Chinese characters, garbled characters are often encountered. . PHP provides some built-in functions for character transcoding, such as iconv and mb_convert_encoding.

iconv function can convert a string from one character set to another. The following is a simple example to convert a UTF-8 encoded string to GBK encoding:

$str = "中文";
$str_gbk = iconv("UTF-8", "GBK", $str);
echo $str_gbk; // 输出：中文（GBK编码）

The mb_convert_encoding function can also implement character transcoding, and it supports more character sets and options. The following is an example of using the mb_convert_encoding function:

$str = "中文";
$str_gbk = mb_convert_encoding($str, "GBK", "UTF-8");
echo $str_gbk; // 输出：中文（GBK编码）

The above are some examples of using PHP built-in functions to develop gadgets. Although these functions may not be complex, using PHP built-in functions can improve development efficiency and reduce the amount of code. Hope this article is helpful to everyone.

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