Crystal report: Problem in setting top property for horizontal Line

Question

Hi everybody, I have some line objects in my report. I want to change their positions dynamically.( My code is in C# ) I tried to use Top property in this way: ((LineObject)HeaderReport.PageHeaderSection1.ReportObjects[caption]).Top = 100 ; but it generated this exception: The line object's coordinates are not valid. Only vertical or horizontal lines are supported. Is there any other way to move a horizontal line instead of setting its top? I hope someone help me to solve it :) Thanks, Mehrvash