How to find if Dataset contains a value

SSAS and SSRS
1

I am using a textbox on my form like a checkbox. It the ID is returned in my dataset I use an "X" into the textbox. How do I do this?

2

You haven't supplied much detail here so....

textbox.Text = (DataRow["ID"].length > 0 ? "X" : ""); // C# (ish)