C#网页 截图

using system.io;
using system.drawing;
using system.drawing.imaging;
using system.threading;
using system.windows.forms;
using system;

namespace consoleapp1
{
    public  class capturewebpage
    {

        public byte[] picbytes; 

        public capturewebpage(string url)
        {
            string bmppath =datetime.now.tostring("yyyymmddhhmmssffff")+".bmp";
            bitmap bmp = new bitmap(1000,10000);
            
            makepicture(url);
            bmp = bytetoimage(picbytes);
            bmp.save(bmppath);
        }
        private void makepicture(string url)
        {
            thread thread = new thread(delegate ()
            {
                using (webbrowser browser = new webbrowser())
                {
                    browser.scrollbarsenabled = true;
                    browser.allownavigation = true;
                    browser.navigate(url);
                    browser.width = 1024;
                    browser.height =10000;
                    browser.documentcompleted += new webbrowserdocumentcompletedeventhandler(documentcompleted);
                    while (browser.readystate != webbrowserreadystate.complete)
                    {
                        system.windows.forms.application.doevents();
                    }

                }
            });
            thread.setapartmentstate(apartmentstate.sta);
            thread.start();
            thread.join();
        }

        private void documentcompleted(object sender, webbrowserdocumentcompletedeventargs e)
        {
            webbrowser browser = sender as webbrowser;
            using (bitmap bitmap = new bitmap(browser.width, browser.height))
            {
                browser.drawtobitmap(bitmap, new system.drawing.rectangle(0, 0, browser.width, browser.height));
                using (memorystream stream = new memorystream())
                {
                    bitmap.save(stream, system.drawing.imaging.imageformat.png);
                    byte[] bytes = stream.toarray();
                    picbytes = bytes;

                }
            }
        }

        public static bitmap bytetoimage(byte[] blob)
        {
            memorystream mstream = new memorystream();
            byte[] pdata = blob;
            mstream.write(pdata, 0, convert.toint32(pdata.length));
            bitmap bm = new bitmap(mstream, false);
            mstream.dispose();
            return bm;
        }
    }
}