我需要使用C＃
将PDF转换为JPEG（或任何其他图像格式为PNG ...）我有PDF的路径，我想获得图像的MemoryStream。
我设法使用Ghostscript和GhostscriptSharp但我被迫创建一个文件，即实际图像，然后读取此文件以创建MemoryStream。
如果没有这一步，我可以这样做吗？
由于
答案 0 :(得分：3)
是的，但您需要使用Ghostscript DLL直接与Ghostscript连接（我假设Windows，因为您提到了C＃）。
最简单的解决方案可能是使用显示设备将内存中的位图发送回父应用程序，然后默认的GS应用程序创建一个窗口和设备上下文，并在其中绘制位图。
您应该能够使用GS应用程序作为起点来了解如何完成此操作，并且您不需要创建自己的设备，这意味着您无需重新编译Ghostscript二进制文件。 / p>
答案 1 :(得分：2)
是的，您可以从Ghostscript.Net rasterize函数创建内存流。这是我在asp.net网站上使用的一个例子。
<?php
Class ExcelWriter
{
var $fp=null;
var $error;
var $state="CLOSED";
var $newRow=false;
/*
* @Params : $file : file name of excel file to be created.
* @Return : On Success Valid File Pointer to file
* On Failure return false
*/
function ExcelWriter($file="")
{
return $this->open($file);
}
/*
* @Params : $file : file name of excel file to be created.
* if you are using file name with directory i.e. test/myFile.xls
* then the directory must be existed on the system and have permissioned properly
* to write the file.
* @Return : On Success Valid File Pointer to file
* On Failure return false
*/
function open($file)
{
if($this->state!="CLOSED")
{
$this->error="Error : Another file is opend .Close it to save the file";
return false;
}
if(!empty($file))
{
$this->fp=@fopen($file,"w+");
}
else
{
$this->error="Usage : New ExcelWriter('fileName')";
return false;
}
if($this->fp==false)
{
$this->error="Error: Unable to open/create File.You may not have permmsion to write the file.";
return false;
}
$this->state="OPENED";
fwrite($this->fp,$this->GetHeader());
return $this->fp;
}
function close()
{
if($this->state!="OPENED")
{
$this->error="Error : Please open the file.";
return false;
}
if($this->newRow)
{
fwrite($this->fp,"</tr>");
$this->newRow=false;
}
fwrite($this->fp,$this->GetFooter());
fclose($this->fp);
$this->state="CLOSED";
return ;
}
//check it
function GetHeader()
{
$header = <<<EOH
<html xmlns:o="urn:schemas-microsoft-com:office:office"
xmlns:x="urn:schemas-microsoft-com:office:excel"
xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=ProgId content=Excel.Sheet>
<!--[if gte mso 9]><xml>
<o:DocumentProperties>
<o:LastAuthor>Sriram</o:LastAuthor>
<o:LastSaved>2005-01-02T07:46:23Z</o:LastSaved>
<o:Version>10.2625</o:Version>
</o:DocumentProperties>
<o:OfficeDocumentSettings>
<o:DownloadComponents/>
</o:OfficeDocumentSettings>
</xml><![endif]-->
<style>
<!--table
{mso-displayed-decimal-separator:"\.";
mso-displayed-thousand-separator:"\,";}
@page
{margin:1.0in .75in 1.0in .75in;
mso-header-margin:.5in;
mso-footer-margin:.5in;}
tr
{mso-height-source:auto;}
col
{mso-width-source:auto;}
br
{mso-data-placement:same-cell;}
.style0
{mso-number-format:General;
text-align:general;
vertical-align:bottom;
white-space:nowrap;
mso-rotate:0;
mso-background-source:auto;
mso-pattern:auto;
color:windowtext;
font-size:10.0pt;
font-weight:400;
font-style:normal;
text-decoration:none;
font-family:Arial;
mso-generic-font-family:auto;
mso-font-charset:0;
border:none;
mso-protection:locked visible;
mso-style-name:Normal;
mso-style-id:0;}
td
{mso-style-parent:style0;
padding-top:1px;
padding-right:1px;
padding-left:1px;
mso-ignore:padding;
color:windowtext;
font-size:10.0pt;
font-weight:400;
font-style:normal;
text-decoration:none;
font-family:Arial;
mso-generic-font-family:auto;
mso-font-charset:0;
mso-number-format:General;
text-align:general;
vertical-align:bottom;
border:none;
mso-background-source:auto;
mso-pattern:auto;
mso-protection:locked visible;
white-space:nowrap;
mso-rotate:0;}
.xl24
{mso-style-parent:style0;
white-space:normal;}
-->
</style>
<!--[if gte mso 9]><xml>
<x:ExcelWorkbook>
<x:ExcelWorksheets>
<x:ExcelWorksheet>
<x:Name>srirmam</x:Name>
<x:WorksheetOptions>
<x:Selected/>
<x:ProtectContents>False</x:ProtectContents>
<x:ProtectObjects>False</x:ProtectObjects>
<x:ProtectScenarios>False</x:ProtectScenarios>
</x:WorksheetOptions>
</x:ExcelWorksheet>
</x:ExcelWorksheets>
<x:WindowHeight>10005</x:WindowHeight>
<x:WindowWidth>10005</x:WindowWidth>
<x:WindowTopX>120</x:WindowTopX>
<x:WindowTopY>135</x:WindowTopY>
<x:ProtectStructure>False</x:ProtectStructure>
<x:ProtectWindows>False</x:ProtectWindows>
</x:ExcelWorkbook>
</xml><![endif]-->
</head>
<body link=blue vlink=purple>
<table x:str border=0 cellpadding=0 cellspacing=0 style='border-collapse: collapse;table-layout:fixed;'>
EOH;
return $header;
}
function GetFooter()
{
return "</table></body></html>";
}
/*
* @Params : $line_arr: An valid array
* @Return : Void
*/
function writeLine($line_arr)
{
if($this->state!="OPENED")
{
$this->error="Error : Please open the file.";
return false;
}
if(!is_array($line_arr))
{
$this->error="Error : Argument is not valid. Supply an valid Array.";
return false;
}
fwrite($this->fp,"<tr>");
foreach($line_arr as $col)
fwrite($this->fp,"<td class=xl24 width=64 >$col</td>");
fwrite($this->fp,"</tr>");
}
/*
* @Params : Void
* @Return : Void
*/
function writeRow()
{
if($this->state!="OPENED")
{
$this->error="Error : Please open the file.";
return false;
}
if($this->newRow==false)
fwrite($this->fp,"<tr>");
else
fwrite($this->fp,"</tr><tr>");
$this->newRow=true;
}
/*
* @Params : $value : Coloumn Value
* @Return : Void
*/
function writeCol($value)
{
if($this->state!="OPENED")
{
$this->error="Error : Please open the file.";
return false;
}
fwrite($this->fp,"<td class=xl24 width=64 >$value</td>");
}
}
?>