问题-仅在文档开始处才允许XML声明 [英] Problem - XML declaration allowed only at the start of the document

问题描述

xml:19558:解析器错误:仅在文档开始处允许XML声明

xml:19558: parser error : XML declaration allowed only at the start of the document

有什么解决方案吗?我正在使用php XMLReader解析一个大型XML文件，但是却收到此错误.我知道该文件的格式不正确，但是我认为无法遍历该文件并删除这些多余的声明.所以任何想法，请帮助

any solutions? i am using php XMLReader to parse a large XML file, but getting this error. i know the file is not well formatted but i think its not possible to go through the file and remove these extra declarations. so any idea, PLEASE HELP

推荐答案

请确保第一个标记之前没有空格. 试试这个:

Make sure there isn't any white space before the first tag. Try this:

    <?php
//Declarations
$file = "data.txt"; //The file to read from.

#Read the file
$fp = fopen($file, "r"); //Open the file
$data = ""; //Initialize variable to contain the file's content
while(!feof($fp)) //Loop through the file, read it till the end.
{
    $data .= fgets($fp, 1024); //append next kb to data
} 
fclose($fp); //Close file
#End read file
$split = preg_split('/(?<=<\/xml>)(?!$)/', $data); //Split each xml occurence into its own string

foreach ($split as $sxml) //Loop through each xml string
{
    //echo $sxml;
    $reader = new XMLReader(); //Initialize the reader
    $reader->xml($sxml) or die("File not found"); //open the current xml string
    while($reader->read()) //Read it
    {
        switch($reader->nodeType)
        {
            case constant('XMLREADER::ELEMENT'): //Read element
                if ($reader->name == 'record')
                {
                    $dataa = $reader->readInnerXml(); //get contents for <record> tag.
                    echo $dataa; //Print it to screen.
                }
            break;
        }
    }
    $reader->close(); //close reader
}
?>

将$ file变量设置为所需的文件.请注意，我不知道这对于4gb文件的效果如何.告诉我是否可以.

Set the $file variable to the file you want. Note I don't know how well this will work for a 4gb file. Tell me if it doesn't.

这是另一种解决方案，它应与较大的文件(读取文件时解析)一起使用会更好.

Here is another solution, it should work better with the larger file (parses as it is reading the file).

<?php
set_time_limit(0);
//Declarations
$file = "data.txt"; //The file to read from.

#Read the file
$fp = fopen($file, "r") or die("Couldn't Open"); //Open the file

$FoundXmlTagStep = 0;
$FoundEndXMLTagStep = 0;
$curXML = "";
$firstXMLTagRead = false;
while(!feof($fp)) //Loop through the file, read it till the end.
{
    $data = fgets($fp, 2);
    if ($FoundXmlTagStep==0 && $data == "<")
        $FoundXmlTagStep=1;
    else if ($FoundXmlTagStep==1 && $data == "x")
        $FoundXmlTagStep=2;
    else if ($FoundXmlTagStep==2 && $data == "m")
        $FoundXmlTagStep=3;
    else if ($FoundXmlTagStep==3 && $data == "l")
    {
        $FoundXmlTagStep=4;
        $firstXMLTagRead = true;
    }
    else if ($FoundXmlTagStep!=4)
        $FoundXmlTagStep=0;

    if ($FoundXmlTagStep==4)
    {
        if ($firstXMLTagRead)
        {
            $firstXMLTagRead = false;
            $curXML = "<xm";
        }
        $curXML .= $data;

        //Start trying to match end of xml
        if ($FoundEndXMLTagStep==0 && $data == "<")
            $FoundEndXMLTagStep=1;
        elseif ($FoundEndXMLTagStep==1 && $data == "/")
            $FoundEndXMLTagStep=2;
        elseif ($FoundEndXMLTagStep==2 && $data == "x")
            $FoundEndXMLTagStep=3;
        elseif ($FoundEndXMLTagStep==3 && $data == "m")
            $FoundEndXMLTagStep=4;
        elseif ($FoundEndXMLTagStep==4 && $data == "l")
            $FoundEndXMLTagStep=5;
        elseif ($FoundEndXMLTagStep==5 && $data == ">")
        {
            $FoundEndXMLTagStep=0;
            $FoundXmlTagStep=0;
            #finished Reading XML
            ParseXML ($curXML);
        }
        elseif ($FoundEndXMLTagStep!=5)
            $FoundEndXMLTagStep=0;
    }
} 
fclose($fp); //Close file
function ParseXML ($xml)
{
    //echo $sxml;
    $reader = new XMLReader(); //Initialize the reader
    $reader->xml($xml) or die("File not found"); //open the current xml string
    while($reader->read()) //Read it
    {
        switch($reader->nodeType)
        {
            case constant('XMLREADER::ELEMENT'): //Read element
                if ($reader->name == 'record')
                {
                    $dataa = $reader->readInnerXml(); //get contents for <record> tag.
                    echo $dataa; //Print it to screen.
                }
            break;
        }
    }
    $reader->close(); //close reader
}
?>

这篇关于问题-仅在文档开始处才允许XML声明的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！