说真的吗？

Seriously?

if(profileimage==null)
     ShowImage(defaultimage);
else
     ShowImage(profileimage);

将数据绑定到 DataList v = vs.110）.aspx> DataList.ItemDataBound事件 [ ^ ]，只需检查 ImageUrl 的图像控制。如果是空白，则分配默认图像。



您也可以使用 JavaScript 执行此操作。请参阅 - 如何在datalist中显示默认图像 [ ^ ] for答案。

While Binding data to the DataList, inside DataList.ItemDataBound Event[^], just check the ImageUrl of the Image Control. If that is blank, then assign the default image.

You can also do this using JavaScript. Refer - How to show default image in datalist[^] for answers.

看到你可以在HTML方面给出条件

See you can give a condition in HTML side

<![CDATA[<%# ((DataBinder.Eval(Container.DataItem,"ImageFilename").ToString()=="") ? " <img src='/Images/Products/"+DataBinder.Eval(Container.DataItem, "DefaulImageFileName")+"' border='0' /> " :" <img src='/Images/Products/"+DataBinder.Eval(Container.DataItem, "ImageFilename")+"' border='0' /> ")%>]]>