Without seeing you actual code, it is difficult to tell what the problem is. Since I don't know how you are filling your grid, I have to give you a concatenated solution:
string strSelect = "SELECT * FROM SplitTrans WHERE nabID='" + TextBox1.Text + "'";
However, you should use Parametrized queries instead, to avoid accidental or deliberate SQL Injection attack. We would need to see the relevant code fragment to tell you how to do that, though.