php 常用自定義方法
阿新 • • 發佈：2018-11-10
主要方法有 檢測 ajax 請求 調整影象尺寸 網址字串轉換成超級連結 URL地址預設 http 字串 解壓縮 Zip 檔案 檔案 Zip 壓縮 建立標籤雲 強制性檔案下載 返回字串相似程度的百分比 截斷文字
強制性檔案下載
// 1. PHP強制性檔案下載 function force_download($file) { if ((isset($file))&&(file_exists($file))) { header("Content-length: ".filesize($file)); header('Content-Type: application/octet-stream'); header('Content-Disposition: attachment; filename="' . $file . '"'); readfile("$file"); } else { echo "No file selected"; } }
建立標籤雲
// 2. PHP建立標籤雲 function getCloud( $data = array(), $minFontSize = 12, $maxFontSize = 30 ) { $minimumCount = min( array_values( $data ) ); $maximumCount = max( array_values( $data ) ); $spread = $maximumCount - $minimumCount; $cloudHTML = ''; $cloudTags = array(); $spread == 0 && $spread = 1; foreach( $data as $tag => $count ) { $size = $minFontSize + ( $count - $minimumCount ) * ( $maxFontSize - $minFontSize ) / $spread; $cloudTags[] = '<a style="font-size: ' . floor( $size ) . 'px' . '" href="#" title="\'' . $tag . '\' returned a count of ' . $count . '">' . htmlspecialchars( stripslashes( $tag ) ) . '</a>'; } return join( "\n", $cloudTags ) . "\n"; } $arr = Array('Actionscript' => 35, 'Adobe' => 22, 'Array' => 44, 'Background' => 43, 'Blur' => 18, 'Canvas' => 33, 'Class' => 15, 'Color Palette' => 11, 'Crop' => 42, 'Delimiter' => 13, 'Depth' => 34, 'Design' => 8, 'Encode' => 12, 'Encryption' => 30, 'Extract' => 28, 'Filters' => 42); echo getCloud($arr, 12, 36);
尋找兩個字串的相似性 返回相似程度的百分比
// 3. PHP尋找兩個字串的相似性 返回相似程度的百分比
// PHP 提供了一個極少使用的 similar_text 函式，但此函式非常有用，用於比較兩個字串並返回相似程度的百分比。
similar_text($string1, $string2, $percent);
//$percent will have the percentage of similarity
使用 Gravatar 通用頭像
// 4. PHP在應用程式中使用 Gravatar 通用頭像 // 隨著 WordPress 越來越普及，Gravatar 也隨之流行。由於 Gravatar 提供了易於使用的 API，將其納入應用程式也變得十分方便。 function show_gravatar($email, $size, $default, $rating) { echo '<！！！！img src="http://www.gravatar.com/avatar.php?gravatar_id='.md5($email). '&default='.$default.'&size='.$size.'&rating='.$rating.'" width="'.$size.'px" height="'.$size.'px" />'; }
在字元斷點處截斷文字
// 5. PHP在字元斷點處截斷文字
// 所謂斷字 (word break)，即一個單詞可在轉行時斷開的地方。這一函式將在斷字處截斷字串。
// Original PHP code by Chirp Internet: www.chirp.com.au
// Please acknowledge use of this code by including this header.
function myTruncate($string, $limit, $break=".", $pad="...") {
// return with no change if string is shorter than $limit
if(strlen($string) <= $limit)
return $string;
// is $break present between $limit and the end of the string?
if(false !== ($breakpoint = strpos($string, $break, $limit))) {
if($breakpoint < strlen($string) - 1) {
$string = substr($string, 0, $breakpoint) . $pad;
}
}
return $string;
}
$short_string=myTruncate($long_string, 100, ' ');
檔案 Zip 壓縮
// 6. PHP檔案 Zip 壓縮
function create_zip($files = array(),$destination = '',$overwrite = false) {
//if the zip file already exists and overwrite is false, return false
if(file_exists($destination) && !$overwrite) { return false; }
//vars
$valid_files = array();
//if files were passed in...
if(is_array($files)) {
//cycle through each file
foreach($files as $file) {
//make sure the file exists
if(file_exists($file)) {
$valid_files[] = $file;
}
}
}
//if we have good files...
if(count($valid_files)) {
//create the archive
$zip = new ZipArchive();
if($zip->open($destination,$overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) {
return false;
}
//add the files
foreach($valid_files as $file) {
$zip->addFile($file,$file);
}
//debug
//echo 'The zip archive contains ',$zip->numFiles,' files with a status of ',$zip->status;
//close the zip -- done!
$zip->close();
//check to make sure the file exists
return file_exists($destination);
}
else
{
return false;
}
}
$files=array('file1.jpg', 'file2.jpg', 'file3.gif');
create_zip($files, 'myzipfile.zip', true);
解壓縮 Zip 檔案
// 7. PHP解壓縮 Zip 檔案
function unzip_file($file, $destination){
// create object
$zip = new ZipArchive() ;
// open archive
if ($zip->open($file) !== TRUE) {
die ('Could not open archive');
}
// extract contents to destination directory
$zip->extractTo($destination);
// close archive
$zip->close();
echo 'Archive extracted to directory';
}
URL 地址預設 http 字串
// 8. PHP為 URL 地址預設 http 字串
if (!preg_match("/^(http|ftp):/", $_POST['url'])) {
$_POST['url'] = 'http://'.$_POST['url'];
}
URL 和 E-mail 地址字串轉換為可點選的超級連結。
// 9. PHP將網址字串轉換成超級連結
function makeClickableLinks($text) {
$text = eregi_replace('(((f|ht){1}tp://)[[email protected]:%_+.~#?&//=]+)', '<a href="\1">\1</a>', $text);
$text = eregi_replace('([[:space:]()[{}])(www.[[email protected]:%_+.~#?&//=]+)','\1<a href="http://\2">\2</a>', $text);
$text = eregi_replace('([_.0-9a-z-][email protected]([0-9a-z][0-9a-z-]+.)+[a-z]{2,3})', '<a href="mailto:\1">\1</a>', $text);
return $text;
}
後臺重新定義影象尺寸 方法為阻塞方式 需要許多時間 此程式碼將有助於瞭解縮圖的邏輯。
// 10. PHP調整影象尺寸
function resize_image($filename, $tmpname, $xmax, $ymax) {
$ext = explode(".", $filename);
$ext = $ext[count($ext)-1];
if($ext == "jpg" || $ext == "jpeg")
$im = imagecreatefromjpeg($tmpname);
elseif($ext == "png")
$im = imagecreatefrompng($tmpname);
elseif($ext == "gif")
$im = imagecreatefromgif($tmpname);
$x = imagesx($im);
$y = imagesy($im);
if($x <= $xmax && $y <= $ymax)
return $im;
if($x >= $y) {
$newx = $xmax;
$newy = $newx * $y / $x;
} else {
$newy = $ymax;
$newx = $x / $y * $newy;
}
$im2 = imagecreatetruecolor($newx, $newy);
imagecopyresized($im2, $im, 0, 0, 0, 0, floor($newx), floor($newy), $x, $y);
return $im2;
}
檢測 ajax 請求 主要判斷的是頭部資訊 HTTP_X_REQUESTED_WITH == xmlhttprequest
// 11. PHP檢測 ajax 請求
if( !emptyempty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest'){
//If AJAX Request Then
}else{
//something else
}