如何在C＃窗体窗体的ms访问图像值中插入空值？

我想让那个用户选择图像然后在ms访问中插入该图像，如果没有选择则插入空值或其他我不知道的东西。



我尝试过：



i这样做：

i want to make that user select image then insert that image in ms access and if not select then insert null value or something else that i don't know.

What I have tried:

i do this:

if(pb_new.image.toString() == "")
{
   param[0] = new oledbparameter("@Image",oledbtype.varbinary);
   param.value = "" or string.empty() 
}
else
{
   param[0] = new oledbparameter("@Image",oledbtype.varbinary);
   param[0].value = image;
}

有照片框，我给出了名称pb_new，并且有存储图像内存分配和其他东西的图​​像。

there is picturebox which i give name pb_new and there is image which store image memory allocation and other things.