How to Execute Page_Load() in Page's Base Class?

问题

I have the following PerformanceFactsheet.aspx.cs page class

public partial class PerformanceFactsheet : FactsheetBase
{
    protected void Page_Load(object sender, EventArgs e)
    {
        // do stuff with the data extracted in FactsheetBase
        divPerformance.Controls.Add(this.Data);
    }
}

where FactsheetBase is defined as

public class FactsheetBase : System.Web.UI.Page
{
    public MyPageData Data { get; set; } 
    protected void Page_Load(object sender, EventArgs e)
    {
        // get data that's common to all implementors of FactsheetBase
        // and store the values in FactsheetBase's properties
        this.Data = ExtractPageData(Request.QueryString["data"]);            
    }
}

The problem is that FactsheetBase's Page_Load is not executing.

Can anyone tell me what I'm doing wrong? Is there a better way to get the result I'm after?

Thanks

回答1:

We faced the similar problem, All you need to do is just register the handler in the constructor. :)

public class FactsheetBase : System.Web.UI.Page 
{ 

    public FactsheetBase()
    {
        this.Load += new EventHandler(this.Page_Load);
    }

    public MyPageData Data { get; set; }  
    protected void Page_Load(object sender, EventArgs e) 
    { 
        // get data that's common to all implementors of FactsheetBase 
        // and store the values in FactsheetBase's properties 
        this.Data = ExtractPageData(Request.QueryString["data"]);             
    } 
}

Another approach would be to override OnLoad() which is less preferred.

public class FactsheetBase : System.Web.UI.Page 
{ 

    public FactsheetBase()
    {
    }

    public MyPageData Data { get; set; }  
    protected override void OnLoad(EventArgs e)
    {
        //your code
        // get data that's common to all implementors of FactsheetBase 
        // and store the values in FactsheetBase's properties 
        this.Data = ExtractPageData(Request.QueryString["data"]);             

        base.OnLoad(e);
    }
}

回答2:

Instead of a Page_Load() method, override OnLoad() and call base.OnLoad() in PerformanceFactsheet

回答3:

Uhm, I maybe wrong, but I believe this is due to inheritance: you are overwriting the FactsheetBase Page_Load method in the derived class.

In order to have it executed you should do something like

public partial class PerformanceFactsheet : FactsheetBase
{
    protected void Page_Load(object sender, EventArgs e)
    {
        base.Page_Load( sender, e );
        // do stuff with the data extracted in FactsheetBase
        divPerformance.Controls.Add(this.Data);
    }
}

EDIT: n8wrl definitely gave you a cleaner solution (I am not a ASPX programmer).

回答4:

try this one

 public partial class PerformanceFactsheet : FactsheetBase
{
    public PerformanceFactsheet()
    {
        this.Load += new EventHandler(this.Page_Load);
    }

    protected void Page_Load(object sender, EventArgs e)
    {            
        divPerformance.Controls.Add(this.Data);
    }
}

public abstract class FactsheetBase : System.Web.UI.Page
{
    public MyPageData Data { get; set; }
    public FactsheetBase()
    {
        this.Load += new EventHandler(this.Page_Load);
    }

    new protected void Page_Load(object sender, EventArgs e)
    {            
        this.Data = ExtractPageData(Request.QueryString["data"]);
    }
}

回答5:

try this one:

     public partial class PerformanceFactsheet : FactsheetBase
{
    protected override void Page_Load(object sender, EventArgs e)
    {
base.Page_Load(sender, e);
        // do stuff with the data extracted in FactsheetBase
        divPerformance.Controls.Add(this.Data);
    }
}

public class FactsheetBase : System.Web.UI.Page
{
    public MyPageData Data { get; set; } 
    protected virtual void Page_Load(object sender, EventArgs e)
    {
        // get data that's common to all implementors of FactsheetBase
        // and store the values in FactsheetBase's properties
        this.Data = ExtractPageData(Request.QueryString["data"]);            
    }
}

回答6:

Make the page load public, and call it in a manner like this from the other page:

this.myPageOrUserControl.Page_Load(null, EventArgs.Empty);

来源：https://stackoverflow.com/questions/2737092/how-to-execute-page-load-in-pages-base-class