我写了这些行,但我有 NullReferenceException。请帮我解决这个问题!
string FullPath = TempPath + FileName;
System.Drawing.Image Adimg = null;
Adimg = System.Drawing.Image.FromFile(MapPath(FullPath));
我将这些行放入 Public bool 方法中,TempPath 是类属性,FileName 是该方法的输入。
exception Detail:
System.NullReferenceException was unhandled by user code
Message="Object reference not set to an instance of an object."
Source="System.Web"
StackTrace:
at System.Web.UI.Page.MapPath(String virtualPath)
at FileIO.HasValidAttributes(String FileName) in g:\MyProjects\ASP.net Projects\ADBridge\adengine2\App_Code\FileIO.cs:line 44
at UploadPage.<Page_Load>b__0(Object sender1, EventArgs e1) in g:\MyProjects\ASP.net Projects\ADBridge\adengine2\UploadPage.aspx.cs:line 29
at System.Web.UI.WebControls.Button.OnClick(EventArgs e)
at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)
at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
InnerException:
我没有时间!
最佳答案
尝试在服务器对象上调用 MapPath:
HttpContext.Current.Server.MapPath(FullPath)
关于c# - 你调用的对象是空的?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/885268/