Today I came across a situation where I was trying to set an ASP.NET UserControl to be Control.Visible = true, and try as I might, the call was failing. Here's what I did in the immediate window in Visual Studio.
MyControl.Visible = true;
MyControl.Visible; // output: false;
I almost bashed my head against my keyboard. It turns out that 'Visible' behaves like a property, not a field. You can set it to true, but it only returns true if the control is actually visible on the page. In my case, the control was not visible because I had set
ParentControl.Visible = false;
on Page_Load. I was trying to set MyControl.Visible to true on postback, but since ParentControl had not been explicitly set to true, MyControl.Visible was still returning false. I set
ParentControl.Visible = true;
et voila! MyControl.Visible immediately returned true.
Lesson: if you're trying to set your control's Visible property to true, and it's still returning false, check the parent controls and see whether those might not have their visibility set to false.
MyControl.Visible = true;
MyControl.Visible; // output: false;
I almost bashed my head against my keyboard. It turns out that 'Visible' behaves like a property, not a field. You can set it to true, but it only returns true if the control is actually visible on the page. In my case, the control was not visible because I had set
ParentControl.Visible = false;
on Page_Load. I was trying to set MyControl.Visible to true on postback, but since ParentControl had not been explicitly set to true, MyControl.Visible was still returning false. I set
ParentControl.Visible = true;
et voila! MyControl.Visible immediately returned true.
Lesson: if you're trying to set your control's Visible property to true, and it's still returning false, check the parent controls and see whether those might not have their visibility set to false.
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