图片下载实现

Controller：

　　 @RequestMapping("/forecastProduct/{dirName}-{imgName}.png")
    @ResponseBody
    public void downloadImg(@PathVariable(value = "dirName") String dirName, @PathVariable(value = "imgName") String imgName,
                             HttpServletRequest request, HttpServletResponse response) throws Exception{
        response.setHeader("Content-Type","application/x-png");
        response.setHeader("Content-Disposition", dirName+"-"+imgName+".png");
//        response.setContentType("image/png");
        String imgPath = dir + dirName + "/" + imgName;
        BufferedImage bi = ImageIO.read(new File(imgPath));
        ImageIO.write(bi, "png", response.getOutputStream());
    }

页面：

<iframe id="img-download" style=“display:none”  src=""></iframe>

js：

$('#img-download').attr('src','/dwjc/forecastProduct/'+dirName+'-'+imgName+'.png');