如何一次执行一个类并使用ASP.net页中的数据

Question

I have the following class ( UCNewWorkFlow ) which calls a cache database and retrieves rows and adds it to a string array:

public partial class UCNewWorkflow : System.Web.UI.Page
{
    private string Connectioncacha = "";

    public UCNewWorkflow()
    {
        int temp;

        if (IsItWorkDay(DateTime.Now))
        {
            temp = 21;
        }
        else
        {
            temp = 17;
        }

        try
        {
            CacheConnection CacheConnect = new CacheConnection();
            CacheConnect.ConnectionString = Connectioncacha;
            CacheConnect.Open();

            String SQLtext = @"";

            DataTable table = new DataTable();
            CacheCommand Command = new CacheCommand(SQLtext, CacheConnect);
            CacheDataReader Reader = Command.ExecuteReader();
            string[] inArr = new string[4];
            int k = 0;

            if (Reader.HasRows)
            {
                while (Reader.Read())
                {
                    inArr[k] = Reader["NotYetSeen"].ToString();
                    returnTime(Convert.ToInt32(inArr[k]));
                    k++;
                }
            }
        }
        catch (Exception ce)
        {
        }
    }

    public string returnTime(int inHowMany)
    {
        string strTime = "";

        double future = 0;

        DateTime dt = DateTime.Now;
        if (inHowMany / 2.0 <= 1)
        {
            strTime = "15 mins";
        }
        else if (inHowMany == 0)
        {
            strTime = "<15 mins";
        }
        else if (inHowMany / 2.0 > 1)
        {
            future = Math.Ceiling((inHowMany / 2.0)) * 15;

            DateTime tempdate = dt.AddMinutes(future);

            TimeSpan result = tempdate - DateTime.Now;

            strTime = ToReadableString(result);
        }

        return strTime;
    }
}

The result of the SQL query:

I have the following labels in my ASP.net page:

<asp:Label ID="lblFirstRow" runat="server" Text="Label"></asp:Label>
<asp:Label ID="lblSecondRow" runat="server" Text="Label"></asp:Label>
<asp:Label ID="lblThirdRow" runat="server" Text="Label"></asp:Label>
<asp:Label ID="lblFourthRow" runat="server" Text="Label"></asp:Label>

The code-behind for the ASP.net page:

protected void Page_Load(object sender, EventArgs e)
{
    UCNewWorkflow uc = new UCNewWorkflow();
}

At the moment, I can't access the label from the class file.

How can I modify the code so, I have to call the class once and it will populate all four labels.

Answer 1

You are trying to perform this database query during the page's constructor, so it is too early in the ASP.NET Web Forms page lifecycle to have access to those arrays. Those labels do not exist when your constructor is called; they are created during the page initialization event.

As NicoTek suggested, using the Page_Load event handler is a good way of updating these labels. However, if you do it his way, I do not see a reason why your class is inheriting from System.Web.UI.Page, I would recommend refactoring your code so that this and any other database operations exist in another class. This will allow you to reuse code and prevent clutter and repetition in your code-behind files.

Answer 2

It looks to me that you want to return the string array inArr as a property of your UCNewWorkflow class and then bind this to a repeater on the Page_Load of your code-behind as suggested by @NicoTek.

Your Repeater definition on the code-in-front should contain just one Label definition and then as data is bound to the Repeater a new instance of the label is created for each element in your string array.

More details on repeaters can be found at http://www.w3schools.com/aspnet/aspnet_repeater.asp

Answer 3

you could do

protected void Page_Load(object sender, EventArgs e)
{
    UCNewWorkflow uc = new UCNewWorkflow();
    lblFirstRow.Text = "someString"
}