Checking if object on page exists

[tshad]

How do you check to see if object exists before accessing it?

For example, I may have an object that I make visible and invisible and I
need to make sure it exists as I am putting this code in a User Control.

UserLoggedOn.visible = true

If this doesn't exists, I get an error.

So how do I test for the object (vb.net and C#) before doing this code?

Thanks,

Tom

 

[Guest]

If(UserLoggedOn != null){
UserLoggedOn.visible = true;
}

 

[bruce barker \(sqlwork.com\)]

if (UserLoggedOn != null) UserLoggedOn.visible = true;

-- bruce (sqlwork.com)

 

[michaelkb]

Try:
if(Page.FindControl("myobjectid")!=null) // It's there

 

[tshad]

Try:
if(Page.FindControl("myobjectid")!=null) // It's there

William mentions:

If(UserLoggedOn != null){
UserLoggedOn.visible = true;
}

Which is better or is it 6 of one...?

Thanks,

Tom

 

[michaelkb]

Agreed...

If(UserLoggedOn != null){
UserLoggedOn.visible = true;
}

 

[michaelkb]

Well, I say that... unless you have a direct reference to the object,
you will need to do the FindControl. If it's directly accessible by
programmatic means, you wouldn't have to.

 

[Hans Kesting]

Try:

if(Page.FindControl("myobjectid")!=null) // It's there

Not always: if "myobjectid" is a "grandchild" (child of another control
on the page) or deeper, then FindControl will not find it as it
searches only through the direct children.

Hans Kesting