Question

我一直在创建一个UI面板，并为界面输入提供动态数据。为此我想要一个基于用户选择的几个SQL查询的valus的SQL查询过滤器。

原型：我生成了面板并且数据显示没有问题，但是因为我不知道在查看第一个查询之前我将拥有多少个过滤器，因此我在过滤器上动态生成checkboxes和dropdowns 。

我遇到的问题是我无法在下拉列表或复选框中访问用户选择的值。

我为每个元素分配了唯一的ID，因此最快的解决方案是getElementByID的c＃等价物？

我将在下面发布一些代码：

protected string SQConnWhere(string TableName = "Nonya", string FieldName = "Error!!!", int i=0)
{
    string ConnectionString = "real string removed";
    cmdText = @"SELECT DISTINCT " + FieldName + " FROM tablenamechangedfromrealonetoprotectthe innocent";

    Label myLabel = new Label();
    Label myLabelA = new Label();
    CheckBox myCheckBox = new CheckBox();
    DropDownList myList = new DropDownList();

    myList.ID     = "myList"     + i;
    myCheckBox.ID = "myCheckBox" + i;
    myLabel.ID    = "myLabel"    + i;
    myLabelA.ID   = "myLabelA"   + i;

    myLabel.Text = FieldName;
    PlaceHolder1.Controls.Add(myLabel);
    PlaceHolder1.Controls.Add(new LiteralControl("<br />"));
    PlaceHolder1.Controls.Add(myList);
    myCheckBox.Text = "Use This Field in Filter?";

    using (SqlConnection conn = new SqlConnection(ConnectionString))
    {
        try
        {
            SqlDataAdapter adapter = new SqlDataAdapter(cmdText, conn);
            DataSet ds2 = new DataSet();
            adapter.Fill(ds2);                                       

            myList.DataSource = ds2;                    
            myList.DataTextField = FieldName;
            myList.DataBind();
            ViewState["Data"] = ds2;                  
        }
        catch (Exception e)
        {
            Console.WriteLine("{0} Exception caught.", e);
        }
    }            

    PlaceHolder1.Controls.Add(myCheckBox);
    PlaceHolder1.Controls.Add(new LiteralControl("<br />"));
    //May not need this? 
    //filterList.Add(FieldName);

    myLabelA.Text = cmdText;                        
    PlaceHolder1.Controls.Add(myLabelA);
    PlaceHolder1.Controls.Add(new LiteralControl("<br />"));
    PlaceHolder1.Controls.Add(new LiteralControl("<br />"));


    //myCheckBox.CheckedChanged += new EventHandler(UpdatemyCheckBox);
    //pnlCheckList.Controls.Add(myCheckBox);

    // register the control to cause asynchronous postbacks
    //ScriptManager.GetCurrent(this).RegisterAsyncPostBackControl(myCheckBox);

    //Label4.Text = FieldName;
    return cmdText;
}

P.S。这是我的第一篇文章，尽管长时间浏览网站，感谢迄今为止的所有帮助!!!

Answer 1

我用

解决了它

    ManualSQConnWhere(DropDownList1, myTable, "Run_ID", CheckBox1);
    ManualSQConnWhere(DropDownList2, myTable, "Job_Status", CheckBox2);
    ManualSQConnWhere(DropDownList3, myTable, "Job_Plan", CheckBox3);

    protected string ManualSQConnWhere(DropDownList myList, string TableNameWeb2, string FieldName, CheckBox myCheckBox)
    {
        string ConnectionString = "Data Source=xxxxx;Initial Catalog=xxxxx;Integrated Security=True";
        cmdText = @"SELECT DISTINCT " + FieldName + " FROM " + TableNameWeb2;
        DataSet dbWeb2 = new DataSet();
        myList.AutoPostBack = false;
        //myList.ViewStateMode = ViewStateMode.Enabled;

        using (SqlConnection conn = new SqlConnection(ConnectionString))
        {
            try
            {
                SqlDataAdapter adapter = new SqlDataAdapter(cmdText, conn);
                adapter.Fill(dbWeb2);

                ViewState["Data"] = dbWeb2;
            }
            catch (Exception e)
            {
                Console.WriteLine("{0} Exception caught.", e);
            }
        }
        myList.AppendDataBoundItems = true;
        myList.DataSource = dbWeb2;
        myList.DataTextField = FieldName;
        myList.Items.Add(new ListItem("<None Selected>", string.Empty));

        if (dbWeb2.Tables.Count > 0)
        {
            myList.DataBind();
        }
        else
        {
            Label1.Text = "Error on the SQL Query" + cmdText;
            return cmdText;
        }

        myCheckBox.Text = FieldName;
        return cmdText;
    }

此代码传达了下拉列表，我只是为它们输入了标签

获取c＃中动态生成的下拉/复选框的选定值

1 个答案: