change visibility with expression in Microsoft Report rdlc

i need to change the visibility of a image in my report. 开发者_开发百科For that i'm using an expression. For default i want it set to true, and when i'm printing i set the parameter to false so the image doen't show up. Problem is, image never show's up.

=CBool(Parameters!ShowImage.Value)

c# (the parameter i send when creating the report)

p[27] = new ReportParameter("ShowImage", "True");
            this.reportViewer1.LocalReport.SetParameters(p);

Thanks in advance

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You're setting the Hidden property of the control in the RDLC right?

Try =(Parameters!ShowImage.value="False")