使用 PHP 在 PDF 文件中搜索字符串

Question

我想以strstr()的方式从pdf文件中搜索字符串。但是，当pdf被阅读为纯文本时，它会给你一个无法理解的垃圾。我该怎么做？

也许pdflib有一些解决方案，但我的托管服务提供商没有帮助我安装它。

Answer 1

使用上一个响应中的链接，我对代码进行了一些更改，以满足我的需求，即搜索和替换，文章中的函数不需要额外的库，但您确实需要 REPLACE 部分的 FPDI 库。

现在这段代码也不是完美的，但对于任何搜索类似内容的人来说，这都是一个好的开始。

该脚本存在的主要问题是新数据被覆盖在原始pdf模板的一种图像上，这意味着如果您尝试用5行文本替换2行文本，它不会插入文本，而是覆盖2行加3行。这也意味着您尝试覆盖的任何内容都必须具有匹配的背景。

但是对于一些基本需求，例如有一个很好的商业提案或像模板一样在pdf上的报价，这个脚本可以覆盖日期或客户端名称，所有这些都在php应用程序中。

function decodeAsciiHex($input) {
    $output = "";
    $isOdd = true;
    $isComment = false;
    for($i = 0, $codeHigh = -1; $i < strlen($input) && $input[$i] != '>'; $i++) {
        $c = $input[$i];
        if($isComment) {
            if ($c == 'r' || $c == 'n')
                $isComment = false;
            continue;
        }
        switch($c) {
            case '': case 't': case 'r': case 'f': case 'n': case ' ': break;
            case '%': 
                $isComment = true;
            break;
            default:
                $code = hexdec($c);
                if($code === 0 && $c != '0')
                    return "";
                if($isOdd)
                    $codeHigh = $code;
                else
                    $output .= chr($codeHigh * 16 + $code);
                $isOdd = !$isOdd;
            break;
        }
    }
    if($input[$i] != '>')
        return "";
    if($isOdd)
        $output .= chr($codeHigh * 16);
    return $output;
}
function decodeAscii85($input) {
    $output = "";
    $isComment = false;
    $ords = array();
    for($i = 0, $state = 0; $i < strlen($input) && $input[$i] != '~'; $i++) {
        $c = $input[$i];
        if($isComment) {
            if ($c == 'r' || $c == 'n')
                $isComment = false;
            continue;
        }
        if ($c == '' || $c == 't' || $c == 'r' || $c == 'f' || $c == 'n' || $c == ' ')
            continue;
        if ($c == '%') {
            $isComment = true;
            continue;
        }
        if ($c == 'z' && $state === 0) {
            $output .= str_repeat(chr(0), 4);
            continue;
        }
        if ($c < '!' || $c > 'u')
            return "";
        $code = ord($input[$i]) & 0xff;
        $ords[$state++] = $code - ord('!');
        if ($state == 5) {
            $state = 0;
            for ($sum = 0, $j = 0; $j < 5; $j++)
                $sum = $sum * 85 + $ords[$j];
            for ($j = 3; $j >= 0; $j--)
                $output .= chr($sum >> ($j * 8));
        }
    }
    if ($state === 1)
        return "";
    elseif ($state > 1) {
        for ($i = 0, $sum = 0; $i < $state; $i++)
            $sum += ($ords[$i] + ($i == $state - 1)) * pow(85, 4 - $i);
        for ($i = 0; $i < $state - 1; $i++)
            $ouput .= chr($sum >> ((3 - $i) * 8));
    }
    return $output;
}
function decodeFlate($input) {
    return @gzuncompress($input);
}
function getObjectOptions($object) {
    $options = array();
    if (preg_match("#<<(.*)>>#ismU", $object, $options)) {
        $options = explode("/", $options[1]);
        @array_shift($options);
        $o = array();
        for ($j = 0; $j < @count($options); $j++) {
            $options[$j] = preg_replace("#s+#", " ", trim($options[$j]));
            if (strpos($options[$j], " ") !== false) {
                $parts = explode(" ", $options[$j]);
                $o[$parts[0]] = $parts[1];
            } else
                $o[$options[$j]] = true;
        }
        $options = $o;
        unset($o);
    }
    return $options;
}
function getDecodedStream($stream, $options) {
    $data = "";
    if (empty($options["Filter"]))
        $data = $stream;
    else {
        $length = !empty($options["Length"]) ? $options["Length"] : strlen($stream);
        $_stream = substr($stream, 0, $length);
        foreach ($options as $key => $value) {
            if ($key == "ASCIIHexDecode")
                $_stream = decodeAsciiHex($_stream);
            if ($key == "ASCII85Decode")
                $_stream = decodeAscii85($_stream);
            if ($key == "FlateDecode")
                $_stream = decodeFlate($_stream);
        }
        $data = $_stream;
    }
    return $data;
}
function getDirtyTexts(&$texts, $textContainers) {
    for ($j = 0; $j < count($textContainers); $j++) {
        if (preg_match_all("#[(.*)]s*TJ#ismU", $textContainers[$j], $parts))
            $texts = array_merge($texts, @$parts[1]);
        elseif(preg_match_all("#Tds*((.*))s*Tj#ismU", $textContainers[$j], $parts))
            $texts = array_merge($texts, @$parts[1]);
    }
}
function getCharTransformations(&$transformations, $stream) {
    preg_match_all("#([0-9]+)s+beginbfchar(.*)endbfchar#ismU", $stream, $chars, PREG_SET_ORDER);
    preg_match_all("#([0-9]+)s+beginbfrange(.*)endbfrange#ismU", $stream, $ranges, PREG_SET_ORDER);
    for ($j = 0; $j < count($chars); $j++) {
        $count = $chars[$j][1];
        $current = explode("n", trim($chars[$j][2]));
        for ($k = 0; $k < $count && $k < count($current); $k++) {
            if (preg_match("#<([0-9a-f]{2,4})>s+<([0-9a-f]{4,512})>#is", trim($current[$k]), $map))
                $transformations[str_pad($map[1], 4, "0")] = $map[2];
        }
    }
    for ($j = 0; $j < count($ranges); $j++) {
        $count = $ranges[$j][1];
        $current = explode("n", trim($ranges[$j][2]));
        for ($k = 0; $k < $count && $k < count($current); $k++) {
            if (preg_match("#<([0-9a-f]{4})>s+<([0-9a-f]{4})>s+<([0-9a-f]{4})>#is", trim($current[$k]), $map)) {
                $from = hexdec($map[1]);
                $to = hexdec($map[2]);
                $_from = hexdec($map[3]);
                for ($m = $from, $n = 0; $m <= $to; $m++, $n++)
                    $transformations[sprintf("%04X", $m)] = sprintf("%04X", $_from + $n);
            } elseif (preg_match("#<([0-9a-f]{4})>s+<([0-9a-f]{4})>s+[(.*)]#ismU", trim($current[$k]), $map)) {
                $from = hexdec($map[1]);
                $to = hexdec($map[2]);
                $parts = preg_split("#s+#", trim($map[3]));
                for ($m = $from, $n = 0; $m <= $to && $n < count($parts); $m++, $n++)
                    $transformations[sprintf("%04X", $m)] = sprintf("%04X", hexdec($parts[$n]));
            }
        }
    }
}
function getTextUsingTransformations($texts, $transformations) {
    $document = "";
    for ($i = 0; $i < count($texts); $i++) {
        $isHex = false;
        $isPlain = false;
        $hex = "";
        $plain = "";
        for ($j = 0; $j < strlen($texts[$i]); $j++) {
            $c = $texts[$i][$j];
            switch($c) {
                case "<":
                    $hex = "";
                    $isHex = true;
                break;
                case ">":
                    $hexs = str_split($hex, 4);
                    for ($k = 0; $k < count($hexs); $k++) {
                        $chex = str_pad($hexs[$k], 4, "0");
                        if (isset($transformations[$chex]))
                            $chex = $transformations[$chex];
                        $document .= html_entity_decode("&#x".$chex.";");
                    }
                    $isHex = false;
                break;
                case "(":
                    $plain = "";
                    $isPlain = true;
                break;
                case ")":
                    $document .= $plain;
                    $isPlain = false;
                break;
                case "\":
                    $c2 = $texts[$i][$j + 1];
                    if (in_array($c2, array("\", "(", ")"))) $plain .= $c2;
                    elseif ($c2 == "n") $plain .= 'n';
                    elseif ($c2 == "r") $plain .= 'r';
                    elseif ($c2 == "t") $plain .= 't';
                    elseif ($c2 == "b") $plain .= 'b';
                    elseif ($c2 == "f") $plain .= 'f';
                    elseif ($c2 >= '0' && $c2 <= '9') {
                        $oct = preg_replace("#[^0-9]#", "", substr($texts[$i], $j + 1, 3));
                        $j += strlen($oct) - 1;
                        $plain .= html_entity_decode("&#".octdec($oct).";");
                    }
                    $j++;
                break;
                default:
                    if ($isHex)
                        $hex .= $c;
                    if ($isPlain)
                        $plain .= $c;
                break;
            }
        }
        $document .= "n";
    }
    return $document;
}
function pdf2text($filename, $search) {
    $pageNumber = 1;
    $infile = @file_get_contents($filename, FILE_BINARY);
    if (empty($infile))
        return "";
    $transformations = array();    
    preg_match_all("#obj(.*)endobj#ismU", $infile, $objects);
    $objects = @$objects[1];
    for ($i = 0; $i < count($objects); $i++) {
        $texts = array();
        $currentObject = $objects[$i];
        if (preg_match("#stream(.*)endstream#ismU", $currentObject, $stream)) {
            $stream = ltrim($stream[1]);
            $options = getObjectOptions($currentObject);
            if (!(empty($options["Length1"]) && empty($options["Type"]) && empty($options["Subtype"])))
                continue;
            $data = getDecodedStream($stream, $options); 
            if (strlen($data)) {
                if (preg_match_all("#BT(.*)ET#ismU", $data, $textContainers)) {
                    //print_r($textContainers);
                    $textContainers = @$textContainers[1];
                    //print_r($textContainers);print "<br><br>";
                    getDirtyTexts($texts, $textContainers);
                    //print_r($textContainers);
                }else{
                    getCharTransformations($transformations, $data);
                }
            }
            //print "HOJA = ".$pageNumber;
            //$textTransformed = getTextUsingTransformations($texts, $transformations);
            //print $textTransformed."<br><br><br>";
            //print_r($currentObject);
            //print_r($options);
            //print_r($stream);
            //print_r($data);
            //print ($textContainers[0])."<br>";
            //print_r($textContainers);
            //print_r($texts);            
            //print "<br><br><br>";
            $m = array();            
            foreach ($texts as $key => $value) {
                $prearray = array($value);
                //print_r($textContainers[$key]);
                preg_match("//F[0-9]s[0-9][0-9]/",$textContainers[$key],$m);
                if(!empty($m)){
                    $fontSize = array();
                    $fontSize = explode(" ", $m[0]);
                    $fontSize = array_filter($fontSize);
                    //print_r($fontSize);
                }
                $textTransformed = getTextUsingTransformations($prearray, $transformations);
                //print $textTransformed."<br><br><br>";
                $pos = strpos($textTransformed, $search);
                if($pos !== false){
                    $data = NULL;
                    $pos = strpos($textContainers[$key], "Tm");
                    if($pos !== false){
                        $data = substr($textContainers[$key], 0, $pos);
                    }else{
                        $pos = strpos($textContainers[$key], "Td");
                        if($pos !== false){
                            $data = substr($textContainers[$key], 0, $pos);
                        }
                    }
                    if(!empty($data)){
                        $dataArray = array();
                        $dataArray = explode(" ", $data);
                        $dataArray = array_filter($dataArray);
                        $returnArray = array();
                        $returnArray['keyword'] = $search;
                        $returnArray['page'] = $pageNumber;
                        $returnArray['font'] = $fontSize[1];
                        $returnArray['x'] = $dataArray[count($dataArray)];
                        $returnArray['y'] = $dataArray[count($dataArray)+1];                        
                        return $returnArray;
                    }
                }
            }
            $pageNumber++;
        }
    }
    //return getTextUsingTransformations($texts, $transformations);
    return false;
}

现在使用：

我所做的是保存带有一些将被覆盖的"关键字"的pdf模板文件，例如，为了更改模板PDF上的日期，我将关键字放在我想要的位置，@DATE，等等其他关键字。

如果在 pdf 上找不到您要查找的搜索词，则修改后的 pdf2text 函数返回 false。如果找到它，它将返回一个数组，其中包含搜索的关键字、找到它的页面、单词的字体大小以及 X 和 Y 值。

    // initiate FPDI
$pdf = new FPDI('P', 'pt', 'A4');
$pdf->setPrintHeader(false);
// set the source file
$pdffile = "template.pdf";
$numberOfPages = $pdf->setSourceFile($pdffile);
$theReturnedFecha = pdf2text($pdffile, "@DATE");
$theReturnedCliente = pdf2text($pdffile, "@CLIENT");

// import all pages
for($i = 1; $i <= $numberOfPages; $i++){
    $pdf->AddPage();
    $tplIdx = $pdf->importPage($i);
    $pdf->useTemplate($tplIdx);
    if($theReturnedFecha !== false){
        if($theReturnedFecha['page'] == $i){
            $pdf->SetFont('Helvetica');
            $pdf->SetFontSize($theReturnedFecha['font']);
            $pdf->SetTextColor(0, 0, 0);
            $pdf->SetFillColor(255,255,255);
            $pdf->SetXY($theReturnedFecha['x'], ($theReturnedFecha['y']*-1)-$theReturnedFecha['font']);
            $pdf->Cell(0, 0, dateInSpanish("2015-11-04"), 0, 0, 'L', true);
        }
        //print_r($theReturnedFecha);
    }
    if($theReturnedCliente !== false){
        if($theReturnedCliente['page'] == $i){
            $pdf->SetFont('Helvetica');
            $pdf->SetFontSize($theReturnedCliente['font']);
            $pdf->SetTextColor(0, 0, 0);
            $pdf->SetFillColor(255,255,255);
            $pdf->SetXY($theReturnedCliente['x'], ($theReturnedCliente['y']*-1)-$theReturnedCliente['font']);
            $pdf->Cell(0, 0, $x_nombre_cli, 0, 0, 'L', true);
        }
        //print_r($theReturnedFecha);
    }        
}
$pdf->Output();

希望它对任何人有帮助

再见