Gridview1不會回發

Question

更新我有一個GridView與下面的屬性

 AllowSorting="true" 
     AutoGenerateColumns="false" 
     BorderStyle="None" 
     CellPadding="3" 
     CssClass="inboundTbl" 
     EnableModelValidation="True" 
     PageSize="2" 
     OnPageIndexChanging="GridView1_PageIndexChanging" 
     OnRowDataBound="GridView1_RowDataBound" 
     OnSorting="GridView1_Sorting" 
     Width="100%" 
     > 

和一些奇怪的原因，它不喜歡更新，當我試圖某人的排序教程。那麼，這次我正在嘗試一個過濾器教程，我對這個問題非常困惑。

這是有問題的templatefield。

  <asp:TemplateField HeaderText="Current Terminal ID" SortExpression="VUCTID"> 
       <HeaderTemplate> 
        Terminal: 
        <asp:DropDownList ID="ddlTerminal" runat="server" 
        AppendDataBoundItems="true" 
        AutoPostBack="true" 
        OnSelectedIndexChanged="TerminalChanged" 
        > 
         <asp:ListItem Text="ALL" Value="ALL"></asp:ListItem> 
        </asp:DropDownList> 
       </HeaderTemplate> 
       <ItemTemplate> 
        <%# Eval("VUCTID") %> 
       </ItemTemplate> 
      </asp:TemplateField> 

我要求幫助，爲什麼它不會更新，他說，在GridView的動態填充，這會導致數據表返回空值。我不確定那是什麼意思，但自那以後我還沒有收到他的消息。我會發布函數進行過濾，以防出現問題。

protected void Page_Load(object sender, EventArgs e) 
    { 
     if(!IsPostBack){ 
      ViewState["Filter"]="ALL"; 
      BindGridView(); 
      lastUpdated.Text = "Load: " + DateTime.Now; 
     } 
    } 

protected void BindGridView() 
{ 
    string query = @"censored"; 
    using (iDB2Connection conn = new iDB2Connection(connect)) 
    { 
     using (iDB2Command cmd = new iDB2Command(query, conn)) 
     { 
      conn.Open(); 
      iDB2DataAdapter da = new iDB2DataAdapter(cmd); 
      DataSet ds = new DataSet(); 
      da.Fill(ds); 
      DataTable dt = ds.Tables[0]; 
      GridView1.DataSource = ds; 
      //iDB2DataReader reader; 
      //reader = cmd.ExecuteReader(); 
      //GridView1.DataSource = reader; 
      GridView1.DataBind(); 
      GridView1.GridLines = GridLines.Horizontal; 
      DropDownList ddlTerminal = (DropDownList)GridView1.HeaderRow.FindControl("ddlTerminal"); 
      this.BindTerminalList(ddlTerminal); 

     } 
    } 
} 

protected void TerminalChanged(object sender, EventArgs e) 
{ 
    DropDownList ddlTerminal = (DropDownList)sender; 
    ViewState["Filter"] = ddlTerminal.SelectedValue; 
    this.BindGridView(); 
} 

private void BindTerminalList(DropDownList ddlTerminal) 
{ 
    string query = "censored"; 
    using (iDB2Connection conn = new iDB2Connection(connect)) 
    { 
     using (iDB2Command cmd = new iDB2Command(query, conn)) 
     { 
      conn.Open(); 
      iDB2DataAdapter da = new iDB2DataAdapter(); 
      ddlTerminal.DataSource = cmd.ExecuteReader(); 
      ddlTerminal.DataTextField = "VUCTID"; 
      ddlTerminal.DataValueField = "VUCTID"; 
      ddlTerminal.DataBind(); 
     } 
     ddlTerminal.Items.FindByValue(ViewState["Filter"].ToString()).Selected = true; 
    } 
} 

編輯：啊，我很抱歉。通過更新我的意思是它不會過濾gridview。模板中的下拉框將從數據庫中填充，一旦點擊，gridview應該根據選定的下拉項目進行更新和過濾。但是當我點擊它時，頁面會加載，但gridview看起來不受影響。

Answer 1

對於初始回發，濾波器應該是所有：

if(!IsPostBack){ 
    ViewState["Filter"]="ALL"; 
    BindGridView(); 
    lastUpdated.Text = "Load: " + DateTime.Now; 
} 

對於其他回傳，過濾值應設置。查詢應該相應地更新。

string query = @"SELECT * FROM Table1 WHERE Terminal = '" + ViewState["Filter"] + "'"; 

Answer 2

我想你只是刪除「// if（！IsPostBack）{」和「//}」中的註釋，並且您將輸出所需的輸出。

檢查下面的代碼

protected void Page_Load(object sender, EventArgs e) 
{ 
    if(!IsPostBack){ 
    ViewState["Filter"] = "ALL"; 
    BindGridView(); 
    lastUpdated.Text = "Load: " + DateTime.Now; 
    } 
} 
protected void BindGridView() 
{ 
    string query = @""; 
    DataTable dt = new DataTable(); 
    dt.Columns.Add("VUCTID"); 
    if(Convert.ToString(ViewState["Filter"])=="1") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 1; 
    } 
    if (Convert.ToString(ViewState["Filter"]) == "2") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 2; 
    } 
    if (Convert.ToString(ViewState["Filter"]) == "3") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 3; 
    } 
    if (Convert.ToString(ViewState["Filter"]) == "4") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 4; 
    } 
    if (Convert.ToString(ViewState["Filter"]) == "5") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 5; 
    } 
    if (Convert.ToString(ViewState["Filter"]) == "ALL") 
    { 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 1; 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 2; 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 3; 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 4; 
     dt.Rows.Add(); 
     dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 5; 
    } 
    GridView1.DataSource = dt; 
    GridView1.DataBind(); 
    GridView1.GridLines = GridLines.Horizontal; 
    DropDownList ddlTerminal = (DropDownList)GridView1.HeaderRow.FindControl("ddlTerminal"); 
    this.BindTerminalList(ddlTerminal); 
} 

protected void TerminalChanged(object sender, EventArgs e) 
{ 
    DropDownList ddlTerminal = (DropDownList)sender; 
    ViewState["Filter"] = ddlTerminal.SelectedValue.ToString(); 
    this.BindGridView(); 
} 

private void BindTerminalList(DropDownList ddlTerminal) 
{ 
    string query = ""; 
    DataTable dt = new DataTable(); 
    dt.Columns.Add("VUCTID"); 

    dt.Rows.Add(); 
    dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 1; 
    dt.Rows.Add(); 
    dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 2; 
    dt.Rows.Add(); 
    dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 3; 
    dt.Rows.Add(); 
    dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 4; 
    dt.Rows.Add(); 
    dt.Rows[dt.Rows.Count - 1]["VUCTID"] = 5; 
    ddlTerminal.DataSource = dt; 
    ddlTerminal.DataTextField = "VUCTID"; 
    ddlTerminal.DataValueField = "VUCTID"; 
    ddlTerminal.DataBind(); 
    ddlTerminal.Items.FindByValue(ViewState["Filter"].ToString()).Selected = true; 
} 
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e) 
{ 

} 
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e) 
{ 

} 
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e) 
{ 

}