将ASP.Net GridView从一个页面传递到另一个页面

Question

我想将所有gridview值传递到另一个页面,我在PatientDetails.aspx页面中有一个gridview,下面是一个按钮

<asp:GridView ID="gvDoctorList" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1" 
    AllowPaging="True" AllowSorting="True" AutoGenerateEditButton="true" AutoGenerateSelectButton="true"
    AutoGenerateDeleteButton="true" OnSelectedIndexChanged="gvDoctorList_SelectedIndexChanged" OnRowCommand="gvDoctorList_RowCommand">
    <Columns>
        <asp:TemplateField>
            <ItemTemplate>
                <asp:CheckBox runat="server" ID="chk" OnCheckedChanged="chk_CheckedChanged" AutoPostBack="true" />
                <asp:Label runat="server" ID="lblPID" Visible="false" Text='<%# Eval("PatientId") %>'></asp:Label>
                <asp:Button ID="btnSelect" runat="server" Text="Select" CommandName = "Select" />
            </ItemTemplate>
        </asp:TemplateField>

        <asp:BoundField DataField="PatientId" HeaderText="PatientId" SortExpression="PatientId" />
        <asp:BoundField DataField="firstname" HeaderText="firstname" SortExpression="firstname" />
        <asp:BoundField DataField="lastname" HeaderText="lastname" SortExpression="lastname" />                                
        <asp:BoundField DataField="sex" HeaderText="sex" SortExpression="sex" />
    </Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:MyDatabaseConnectionString %>" 
    SelectCommand="SELECT [PatientId],[firstname], [lastname], [sex] FROM [PatientDetails]"></asp:SqlDataSource>
<asp:Button ID="btnformatric" runat="server" Text="formatric3d" OnClick="btnformatric_Click" OnCommand="btnformatric_Command" />

关于PatientDetails.aspx的代码隐藏如下

protected void btnformatric_Click(object sender, EventArgs e)
{
    if (gvDoctorList.SelectedRow != null)
    {
        Server.Transfer("Patientstaticformatrix.aspx");
    }
    else
    {
        ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('Please select a row.')", true);
    }
}

现在在第二页上名为Patientstaticformatrix.aspx,后面的代码如下

protected void Page_Load(object sender, EventArgs e)
{
    if (this.Page.PreviousPage != null)
    {
        GridView gvDoctorList = (GridView)this.Page.PreviousPage.FindControl("gvDoctorList");

        GridViewRow selectedRow = gvDoctorList.SelectedRow;
        Response.Write("PatientId: " + selectedRow.Cells[0].Text + "<br />");
        Response.Write("firstname: " + selectedRow.Cells[1].Text + "<br />");
        Response.Write("lastname: " + selectedRow.Cells[2].Text + "<br />");
    }
}

我在第二页调试了代码.... gvDoctorList的值为null,而且selectedRow显示了nullreference的错误.

你能告诉我错在哪里吗？

Answer 1

正如我也看到你之前的问题，所以我可以建议你一件事，而不是将你的 gridview 保持在会话中（这很昂贵），你可以使用RowCommand事件，在这里之后button我认为你不需要复选框或chk_CheckedChanged事件，你可以将 传递PatientID到下一页，您可以在那里编写查询以将选定的行数据插入到新表中。

 <asp:TemplateField>
       <ItemTemplate>
        <asp:CheckBox runat="server" ID="chk" OnCheckedChanged="chk_CheckedChanged"  
         AutoPostBack="true" />
        <asp:Label runat="server" ID="lblPID" Visible="false" Text='<%# Eval("PatientId") %>'> 
       </asp:Label>
      <asp:Button ID="btnSelect" runat="server" Text="Select" CommandArgument='<%# 
       Eval("PatientId") %>' CommandName = "Select" />
      </ItemTemplate>
    </asp:TemplateField>



 protected void gvDoctorList_RowCommand(object sender, GridViewCommandEventArgs e)
        {
            if (e.CommandName == "select")
            {
                int pID = Convert.ToInt32(e.CommandArgument);
                // either put ID in session and check 
                Session["PatientID"] = Convert.ToString(pID);
                Server.Transfer("Patientstaticformatrix.aspx");
            }
        }

On page_Load 事件

 protected void Page_Load(object sender, EventArgs e)
    {
         string pID = Convert.ToString(Session["PatientID"]);
            if(!string.IsNullOrEmpty(pID))
            {
              int patientID = Convert.ToInt32(pID);
             //Call Stored procedure which will insert this record with this ID
             // to another table
            }    

    }