C#工具:WPF生成图片验证码

1.使用imageformatconverthelper

using system;
using system.collections.generic;
using system.drawing;
using system.linq;
using system.runtime.interopservices;
using system.text;
using system.threading.tasks;
using system.windows;
using system.windows.media;
using system.windows.media.imaging;

namespace yongan_wpf
{
    public class imageformatconverthelper
    {
        [dllimport("gdi32.dll", setlasterror = true)]
        private static extern bool deleteobject(intptr hobject);
        /// <summary>  /// 
        /// 从bitmap转换成imagesource  /// 
        /// </summary>  /// 
        /// <param name="icon"></param>
        /// <returns></returns>  
        public static imagesource changebitmaptoimagesource(bitmap bitmap)
        { //bitmap bitmap = icon.tobitmap();  
            intptr hbitmap = bitmap.gethbitmap();
            imagesource wpfbitmap = system.windows.interop.imaging.createbitmapsourcefromhbitmap(hbitmap, intptr.zero, int32rect.empty, bitmapsizeoptions.fromemptyoptions());
            if (!deleteobject(hbitmap))
            { throw new system.componentmodel.win32exception(); }
            return wpfbitmap;
        }
    }
}

2.使用verifycodehelper

using system;
using system.collections.generic;
using system.drawing;
using system.linq;
using system.text;
using system.threading.tasks;

namespace yongan_wpf
{
    public class verifycodehelper
    {
        public static bitmap createverifycode(out string code)
        { //建立bitmap对象，绘图 
            bitmap bitmap = new bitmap(200, 60); graphics graph = graphics.fromimage(bitmap);
            graph.fillrectangle(new solidbrush(color.white), 0, 0, 200, 60);
            font font = new font(fontfamily.genericserif, 48, fontstyle.bold, graphicsunit.pixel);
            random r = new random(); string letters = "abcdefghijklmnpqrstuvwxyz0123456789";
            stringbuilder sb = new stringbuilder();
            //添加随机的五个字母
            for (int x = 0; x < 5; x++)
            {
                string letter = letters.substring(r.next(0, letters.length - 1), 1);
                sb.append(letter);
                graph.drawstring(letter, font, new solidbrush(color.black), x * 38, r.next(0, 15));
            }
            code = sb.tostring();
            //混淆背景
            pen linepen = new pen(new solidbrush(color.black), 2);
            for (int x = 0; x < 6; x++) graph.drawline(linepen, new point(r.next(0, 199), r.next(0, 59)), new point(r.next(0, 199), r.next(0, 59)));
            return bitmap;
        }
    }
}

3.调用方式 返回code(验证码内容)

        public string getimage()
        {
            string code = "";
            bitmap bitmap = verifycodehelper.createverifycode(out code);
            imagesource imagesource = imageformatconverthelper.changebitmaptoimagesource(bitmap);
            img.source = imagesource;
            return code;
        }