c# - 协助使用混合控件类型进行 SQLDataSource 过滤

Question

我一直在研究数据源过滤，我的页面应用程序的复杂性使我的逻辑陷入泥潭。

我有一个显示来自数据源的 3/17 值的 Gridview。我想针对数据源对 3 个下拉菜单和 3 个复选框运行过滤器。这 3 个 DDL 在索引 0 处具有默认值 String.Empty，并且在页面加载 (!IsPostBack) 时由另一个 DS 填充。

我的问题：

• 当页面加载时，gridview 中没有任何内容。应跳过空 DDL 值。
• 最后一个复选框应表示是否(Part_Catalog.PartCount > 0)。
• 目前过滤器是在数据源中定义的，但是由于上述情况，我需要在cs文件中进行一些处理。我不确定的是如果我需要将整个 DS 移动到后面的代码、过滤器或只是过滤条件。

• 另外我不确定要连接到哪些事件。

  <asp:SqlDataSource ID="SqlDataSource1" 
       runat="server" 
       EnableCaching="true"
       DataSourceMode="DataSet"
       ConnectionString="<%$ ConnectionStrings:inventory_v2ConnectionString %>" 
                   SelectCommand="SELECT ID, OEMPartCode, PartCode2, UsedByOEM, ItemType, GroupType, PartCount, PartDesc, PartComment, PartMin, PartActive, MFRPartNumber, PartCapacity, PreTurnRequired, AssemblyPart, PartImage, PartImage2, NonInventoryPart FROM dbo.Part_Catalog"
                   FilterExpression="UsedByOEM = '{0}' AND ItemType = '{1}' AND GroupType = '{2}' OR     (UsedByOEM = '{0}' OR ItemType = '{1}' OR GroupType = '{2}') OR (UsedByOEM = '{0}' OR     ItemType = '{1}' AND GroupType = '{2}') OR (UsedByOEM = '{0}' AND ItemType = '{1}' OR     GroupType = '{2}')">
      <FilterParameters>
      <asp:ControlParameter Name="UsedByOEM" ControlID="DDL_OEM" PropertyName="SelectedValue" />
      <asp:ControlParameter Name="ItemType" ControlID="DDL_ItemTypes" PropertyName="SelectedValue" />
      <asp:ControlParameter Name="GroupType" ControlID="DDL_GroupTypes" PropertyName="SelectedValue" />
      </FilterParameters>    
  </asp:SqlDataSource>
  
  
    <asp:DropDownList ID="DDL_OEM" runat="server" AutoPostBack="True" AppendDataBoundItems="True"></asp:DropDownList>
     <asp:DropDownList ID="DDL_ItemTypes" runat="server" AutoPostBack="True" AppendDataBoundItems="True"></asp:DropDownList>   
     <asp:DropDownList ID="DDL_GroupTypes" runat="server"   AutoPostBack="True" AppendDataBoundItems="True"></asp:DropDownList>      
     <asp:CheckBox ID="CheckBox1" runat="server" Checked="True" />
     <asp:CheckBox ID="CheckBox2" runat="server" />
     <asp:CheckBox ID="CheckBox3" runat="server" Checked="True" />
  
  protected void BindOEMs()
  {
      SqlConnection connectionString = new SqlConnection(ConfigurationManager.ConnectionStrings["inventory_v2ConnectionString"].ConnectionString);
      connectionString.Open();
      SqlCommand cmd = new SqlCommand("SELECT [Manufacturer], [ID] FROM [Models_OEMs] ORDER BY [Manufacturer]", connectionString);
      SqlDataAdapter da = new SqlDataAdapter(cmd);
      DataSet ds = new DataSet();
      da.Fill(ds);
      connectionString.Close();
      DDL_OEM.DataSource = ds;
      DDL_OEM.DataTextField = "Manufacturer";
      DDL_OEM.DataValueField = "ID";
      DDL_OEM.DataBind();
      DDL_OEM.Items.Insert(0, new ListItem(String.Empty, "0"));
  }            
  

Answer 1

现在想通了。我在 page_load (!isPostBack) 中添加了下面的行，因此过滤器在第一次加载时应用。

if (gvFilter.OEM == null || gvFilter.OEM == 0 ) { Filter_DataSet(null, null); }

使用我的类别创建了一个自定义过滤器对象：

 public class Filters
{
    private int oem;
    private int item;
    private int group;
    private bool active;
    private bool ninventoried;
    private bool stocked;

    public int OEM
    {
        set { oem = value; }
        get { return oem; }
    }
    public int Item
    {
        set { item = value; }
        get { return item; }
    }
    public int Group
    {
        set { group = value; }
        get { return group; }
    }
    public bool Active
    {
        set { active = value; }
        get { return active; }
    }
    public bool Ninventoried
    {
        set { ninventoried = value; }
        get { return ninventoried; }
    }
    public bool Stocked
    {
        set { stocked = value; }
        get { return stocked; }
    }

}

然后我创建了一个方法来将过滤器应用到数据源并将所有过滤器控件事件设置为此方法：

protected void Filter_DataSet(object sender, EventArgs e)
{
    DetailsView1.Visible = false;
    string FEString= String.Empty;
    gvFilter.OEM = Convert.ToInt32(DDL_OEM.SelectedValue);
    gvFilter.Item = Convert.ToInt32(DDL_ItemTypes.SelectedValue);
    gvFilter.Group = Convert.ToInt32(DDL_GroupTypes.SelectedValue);
    if (CheckBox1.Checked == true) { gvFilter.Active = true; } else { gvFilter.Active = false; }
    if (CheckBox2.Checked == true) { gvFilter.Ninventoried = true; } else { gvFilter.Ninventoried = false; }
    if (CheckBox3.Checked == true) { gvFilter.Stocked = true; } else { gvFilter.Stocked = false; }

    if (gvFilter.OEM >0)
    {
        FEString += "UsedByOEM = " + gvFilter.OEM.ToString(); 
    }
    if (gvFilter.Item > 0)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "ItemType = " + gvFilter.Item.ToString();
    }
    if (gvFilter.Group > 0)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "GroupType = " + gvFilter.Group.ToString();
    }
    if (gvFilter.Active == true)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "PartActive = " + gvFilter.Active.ToString();
    }
    if (gvFilter.Active == false)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "PartActive = " + gvFilter.Active.ToString();
    }
    if (gvFilter.Ninventoried == true)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "NonInventoryPart = " + gvFilter.Ninventoried.ToString();
    }
    if (gvFilter.Ninventoried == false)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "NonInventoryPart = " + gvFilter.Ninventoried.ToString();
    }
    if (gvFilter.Stocked == true)
    {
        if (FEString.Length > 0) { FEString += " AND "; }
        FEString += "PartCount > 0 ";
    }
    //if (gvFilter.Stocked == false)
    //{
    //    if (FEString.Length > 0) { FEString += " AND "; }
    //    FEString += "PartCount <= 0 ";
    //}
    SqlDataSource1.FilterExpression = FEString;
}