我有这个问题:
[InvalidOperationException: No data exists for the row / column.]
System.Data.OleDb.OleDbDataReader.DoValueCheck(Int32 ordinal) +1029063
System.Data.OleDb.OleDbDataReader.GetInt32(Int32 ordinal) +12
ASP.addsousvoyage_aspx.hdVoyage_SelectedIndexChanged(Object sender, EventArgs e) in C:\Users\ZiGi\Desktop\VisualDesign\addSousVoyage.aspx:222
System.Web.UI.WebControls.ListControl.OnSelectedIndexChanged(EventArgs e) +111
System.Web.UI.WebControls.DropDownList.RaisePostDataChangedEvent() +134
System.Web.UI.WebControls.DropDownList.System.Web.UI.IPostBackDataHandler.RaisePostDataChangedEvent() +10
System.Web.UI.Page.RaiseChangedEvents() +165
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1485
当我这样做时:
MsgBox(myReader1.GetInt32(0).ToString)
即使 :
MsgBox(myReader1.FieldCount) 返回 1 作为值,并且 field(0) 是整数。
有什么问题 ?