php检测上传excel文件类型的示例代码

<?php
/**
 * Detect upload file type
 * 检测上传文件的excel文件类型
 * @param array $file           
 * @return bool $flag
 * @site www.jb200.com
 */ 
private function detectUploadFileMIME($file) { 
    // 1.through the file extension judgement 03 or 07 
    $flag = 0; 
    $file_array = explode ( ".", $file ["name"] ); 
    $file_extension = strtolower ( array_pop ( $file_array ) ); 
     
    // 2.through the binary content to detect the file 
    switch ($file_extension) { 
        case "xls" : 
            // 2003 excel 
            $fh = fopen ( $file ["tmp_name"], "rb" ); 
            $bin = fread ( $fh, 8 ); 
            fclose ( $fh ); 
            $strinfo = @unpack ( "C8chars", $bin ); 
            $typecode = ""; 
            foreach ( $strinfo as $num ) { 
                $typecode .= dechex ( $num ); 
            } 
            if ($typecode == "d0cf11e0a1b11ae1") { 
                $flag = 1; 
            } 
            break; 
        case "xlsx" : 
            // 2007 excel 
            $fh = fopen ( $file ["tmp_name"], "rb" ); 
            $bin = fread ( $fh, 4 ); 
            fclose ( $fh ); 
            $strinfo = @unpack ( "C4chars", $bin ); 
            $typecode = ""; 
            foreach ( $strinfo as $num ) { 
                $typecode .= dechex ( $num ); 
            } 
            echo $typecode; 
            if ($typecode == "504b34") { 
                $flag = 1; 
            } 
            break; 
    } 
     
    // 3.return the flag 
    return $flag; 
}