C#picturebox控件图片以json格式上传java后台保存

关于winform上传图片到java后端，保存到数据库，有多种方法，本文主要介绍利用picturebox控件，点击按钮上传图片，将图片转化为base64格式,以json格式上传到java后台，再从java端解析，保存到数据库。

上代码:
首先，画面上添加一个picturebox控件，再添加一个button，给button设置click事件-获取到base64格式的字符串。

/// <summary>
/// 图片上传
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnuploadimage_click(object sender, eventargs e)
{
   openfiledialog openfiledialog = new openfiledialog();
   if (openfiledialog.showdialog() == dialogresult.ok)
   {
       //picturebox控件显示图片
       picexppic.load(openfiledialog.filename);
       //获取用户选择文件的后缀名
       string extension = path.getextension(openfiledialog.filename);
       //声明允许的后缀名
       string[] str = new string[] { ".gif", ".jpeg", ".jpg", ".png", ".bmp" };
       if (!str.contains(extension))
       {
           messagebox.show("仅能上传gif,jpge,jpg,png,bmp格式的图片！");
       }
       else
       {
           image img = this.picexppic.image;
           memorystream ms = new memorystream();
           img.save(ms, img.rawformat);
           byte[] bytes = ms.toarray();
           ms.close();
           string strbaser64 = convert.tobase64string(bytes);
           imgstr = "data:image/jpg;base64," + strbaser64;
       }
   }
}

把字符串imgstr拼接成json格式，上传。c#链接java后台代码，后续给出。
java后台接收json:

/**
 * 新增信息
 * @return
 */
@requestmapping(value="/addinfo")
@responsebody
public result addinfo(string strjson,httpservletrequest request){
  jsonobject object = new jsonobject(strjson);
  string base64 = object.getstring("expertpic");
  //转为file格式---获取图片信息
  multipartfile fileexppic = base64tomultipart(base64);             
  result result = new result();
  int ret = 0;
  //格式化字符串
    string base = base64.replace(" ", "+");
  //去掉头部
      string[] basestrs = base.split(",");
      base64decoder decoder = new sun.misc.base64decoder();
      byte[] bytes1;
      string filepath2 = null;
      string filename2 = null;
  try {         
    filepath2 = request.getservletcontext().getrealpath("resources\\\\uploads")+"\\";
    filename2 = "expertpic"+sdf.format(dt)+"."+(fileexppic).getoriginalfilename().substring((fileexppic).getoriginalfilename().lastindexof(".")+1);
    //转化为文件流
    bytes1 = decoder.decodebuffer(basestrs[1]);
        //生成jpeg图片
        string imgfilepath = filepath2+filename2;//新生成的图片
        outputstream out = new fileoutputstream(imgfilepath);   
        out.write(bytes1);
        out.flush();
        out.close();
  } catch (ioexception e1) {
    // todo auto-generated catch block
    e1.printstacktrace();
  }
  file dir = new file(filepath2);
  if(!dir.exists()) {
    dir.mkdirs();
  }
  try {                  
    a a=new a();
    a.temp="";
    ret =this.addservice.addinfo(a);
    if(ret==0) {
      result.setsuccess(false);
      result.seterrmsg("失败！");
    }else {
      result.setsuccess(true);
    }
  } catch (exception e) {
    result.setsuccess(false);
    result.seterrmsg("失败！");
  }
  return result;
}

java base64转化为file方法：

public static multipartfile base64tomultipart(string base64) {
    try {
        string base = base64.replace(" ", "+");
        string[] basestrs = base.split(",");
        base64decoder decoder = new sun.misc.base64decoder();
        byte[] bytes1 = decoder.decodebuffer(basestrs[1]);
        return new base64decodedmultipartfile(bytes1, basestrs[0]);
    } catch (ioexception e) {
        e.printstacktrace();
        return null;
    }
}

保存到数据的是自己拼的图片名称和图片后缀，图片的存储位置在自己指定的项目目录。
至此c#上传图片告一段落