通过判断 限制上传文件的格式为 PDF,docx,xlsx,pptx,potx,vsdx,odt,doc,xls,ppt,vsd,pot,wps,dps,et和txt,rtf文件类型
function checkFileType($filename){ //文件头 $_typecode = array( '3780',//PDF '8075',//.docx,.xlsx,.pptx,.potx,.vsdx,.odt '208207',//.doc,.xls,.ppt,.vsd,.pot,.wps,.dps,.et ); $file = fopen($filename, "rb"); //contents = stream_get_contents($file); //$contents = fread($file, filesize($filename)); $bin = fread($file, 2); //只读2字节 fclose($file); $strInfo = @unpack("C2chars", $bin);// C为无符号整数,网上搜到的都是c,为有符号整数,这样会产生负数判断不正常 $typeCode = intval($strInfo['chars1'].$strInfo['chars2']); exec("file $filename",$output,$return_var);//用linux系统命令file判断上传文件的类型,主要是判断txt,rtf文件类型 $pattern = '/text,/';//rtf和txt文档用file检测都会被检测为text $_count = preg_match($pattern,strrchr($output[0],":")); echo $typeCode; if(in_array($typeCode,$_typecode) || $_count == 1) { return true; }else{ return false; } }