小编Son*_*123的帖子

(例如,根据隐藏值设置rowcolor)

如果你有一个像这样隐藏单元格的gridview

<asp:GridView ID="Timeevents" runat="server" 
        OnRowDataBound="Timeevents_RowDataBound"
        OnRowCommand = "Timeevents_RowCommand"
        AutoGenerateColumns="False"> 
        <columns>
        <asp:BoundField DataField="CaseID" HeaderText="CaseID" Visible = "False" />
        <asp:BoundField DataField="caseworkerID" HeaderText="CwID" Visible = "False" />
        <asp:BoundField DataField="EventTypeID" HeaderText="EvTypeID" Visible = "False" />
        <asp:BoundField DataField="CaseWorker" HeaderText="Case Worker" />
        <asp:BoundField DataField="EventDate" HeaderText="Event Date" />
        <asp:BoundField DataField="Code" HeaderText="Code" />
        <asp:BoundField DataField="TotalUnits" HeaderText="Total Units" />
        <asp:BoundField DataField="EventType" HeaderText="Event Type" />
        <asp:BoundField DataField="UnitCost" HeaderText="Unit Cost" />
        <asp:BoundField DataField="TotalCost" HeaderText="Total Cost"/>
        <asp:TemplateField HeaderText="ADD">
                <ItemTemplate> 
                    <asp:Button  ID="AddUnit" runat="server" Text=" +1 " 
                    CommandName="AddUnit" 
                    CommandArgument='<%# Eval("CaseID")+ ";" + Eval("CaseworkerID")+ …

我很困惑为什么在尝试返回数据集时我得到一个空引用异常.

我有一个处理程序和DBaccess类,就像在nTier架构中一样.

首先,这是我的casefile处理程序/和访问类的一部分工作正常.我包括他们是因为我无法理解为什么这样做而另一部分没有.

public class CaseFileHandler
{
    CaseFileAccess caseaccess = null;

    public CaseFileHandler()
    {
        caseaccess = new CaseFileAccess();
    }



    public DataSet getCaseFileDataset(int caseID)
    {
        return caseaccess.GetCaseFileDataSet(caseID);
    }


    public bool UpdateCasefile(CaseFile casefile)
    {
        return caseaccess.updateCasefile(casefile);
    }     
}

这是访问类.返回数据集的方法工作得很好.

public class CaseFileAccess
{
    const string CONNECTION_STRING = "Data Source = SQLSERVER;Initial Catalog=CaseManager;Integrated Security=SSPI;";

    DBManager _DAL = new DBManager(DataProvider.SqlServer, CONNECTION_STRING);


    public CaseFile GetCaseFile(int caseID)
    {
        CaseFile casefile = new CaseFile();

        _DAL.Open();
        _DAL.CreateParameters(1);
        //stuff
       return casefile;
    }

    public DataSet GetCaseFileDataSet(int caseID)
    {
        _DAL.Open();
        _DAL.CreateParameters(1); …