How to access the item being data bound during ItemDataBound

asp.netrepeater

I want to get at the item that is being data bound, during the ItemDataBound event of an asp:repeater.

I tried the following (which was an unaccepted answer in a stackoverflow question):

protected void myRepeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
    Object dataItem = e.Item.DataItem;
    ...
}

but e.Item.DataItem is null.

How can I access the item being data bound during the event called ItemDataBound. I assume the event ItemDataBound happens when an item is being data bound.

I want to get at the object so I can take steps to control how it is displayed, in addition the object may have additional helpful properties to let me enrich how it is displayed.

Answer

Tool had the right answer. The answer is that e.Item.Data is only valid when e.Item.ItemType is (Item, AlternatingItem). Other times it is not valid. In my case, I was receiving ItemDataBound events during header (or footer) rows, where there is no DataItem:

protected void myRepeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
   // if the data bound item is an item or alternating item (not the header etc)
   if (e.Item.ItemType != ListItemType.Item && 
         e.Item.ItemType != ListItemType.AlternatingItem)
   {
      return;
   }

   Object dataItem = e.Item.DataItem;
   ...
}

Best Answer

Right off the bat I would have to guess you need this:

if (e.Item.ItemType == ListItemType.Item ||
    e.Item.ItemType == ListItemType.AlternatingItem)
{
    //Put stuff here
}

After all, the item itself could be representing a header or footer row.

Access modifiers

From docs.microsoft.com:

public

The type or member can be accessed by any other code in the same assembly or another assembly that references it.

private

The type or member can only be accessed by code in the same class or struct.

protected

The type or member can only be accessed by code in the same class or struct, or in a derived class.

private protected (added in C# 7.2)

The type or member can only be accessed by code in the same class or struct, or in a derived class from the same assembly, but not from another assembly.

internal

The type or member can be accessed by any code in the same assembly, but not from another assembly.

protected internal

The type or member can be accessed by any code in the same assembly, or by any derived class in another assembly.

When no access modifier is set, a default access modifier is used. So there is always some form of access modifier even if it's not set.

`static` modifier

The static modifier on a class means that the class cannot be instantiated, and that all of its members are static. A static member has one version regardless of how many instances of its enclosing type are created.

A static class is basically the same as a non-static class, but there is one difference: a static class cannot be externally instantiated. In other words, you cannot use the new keyword to create a variable of the class type. Because there is no instance variable, you access the members of a static class by using the class name itself.

However, there is a such thing as a static constructor. Any class can have one of these, including static classes. They cannot be called directly & cannot have parameters (other than any type parameters on the class itself). A static constructor is called automatically to initialize the class before the first instance is created or any static members are referenced. Looks like this:

static class Foo()
{
    static Foo()
    {
        Bar = "fubar";
    }
    
    public static string Bar { get; set; }
}

Static classes are often used as services, you can use them like so:

MyStaticClass.ServiceMethod(...);

How to find controls in a repeater header or footer

As noted in the comments, this only works AFTER you've DataBound your repeater.

To find a control in the header:

lblControl = repeater1.Controls[0].Controls[0].FindControl("lblControl");

To find a control in the footer:

lblControl = repeater1.Controls[repeater1.Controls.Count - 1].Controls[0].FindControl("lblControl");

With extension methods

public static class RepeaterExtensionMethods
{
    public static Control FindControlInHeader(this Repeater repeater, string controlName)
    {
        return repeater.Controls[0].Controls[0].FindControl(controlName);
    }

    public static Control FindControlInFooter(this Repeater repeater, string controlName)
    {
        return repeater.Controls[repeater.Controls.Count - 1].Controls[0].FindControl(controlName);
    }
}

Answer

Best Answer

Related Solutions

C# – In C#, what is the difference between public, private, protected, and having no access modifier

Access modifiers

static modifier

How to find controls in a repeater header or footer

With extension methods

Related Topic

`static` modifier