c# - ASP.NET Save Image in ashx handler -

i have simple handler (ashx) receives base 64 encoded image , want save image.

here code:

 sub processrequest(byval context httpcontext) implements ihttphandler.processrequest      dim imageinfo = context.request("imgdata")     dim imagedata string() = imageinfo.split(",")      ' check there 2 parts; ie header , string data.     if imagedata.length < 2         context.response.write("error")         return     end if      ' example of imageinfo     ' data:image/png;base64,ivborw0kggoaaaansuheugaaae...      dim imagetype string = imagedata(0)     dim imagestring string = imagedata(1)      if imagetype <> "data:image/png;base64"         context.response.write("error")         return     end if      imagestring = imagestring.replace(" ", "+")     dim bytes byte()     bytes = convert.frombase64string(imagestring)      dim image system.drawing.image      using ms memorystream = new memorystream(bytes)         image = system.drawing.image.fromstream(ms)     end using     image.save("test", system.drawing.imaging.imageformat.png)  end sub 

however, following error:

an exception of type 'system.runtime.interopservices.externalexception' occurred in system.drawing.dll not handled in user code

additional information: generic error occurred in gdi+

i know image data works in php version. trying convert php asp.net.

/*get file name , image data post*/ $filename = $_post['filename']; $data = $_post['imgdata'];  list( $type, $data ) = explode( ';', $data ); list( $base, $data ) = explode( ',', $data );  /*check image data base64 of png*/ if ( $type === 'data:image/png' && $base === 'base64') {     $data = base64_decode( $data );     file_put_contents( '../pathtosave/' . $filename, $data );     echo 'saved'; } else {     echo 'error'; } 

inspecting image in debugger, appears okay. correctly gets height , width of image.

can see error may be?

i embarrassed. issue "test" not correct file path. testing on local machine , used full path, worked straight away.