Cannot implicitly convert type

Question

 This is my line.
TextBox txtSingleUnitPrice = ((TextBox)gvSender.Rows[e.RowIndex].FindControl("txtSingleUnitPrice"))?(TextBox)gvSender.Rows[e.RowIndex].FindControl("txtSingleUnitPrice"):0;


Error name is Cannot implicitly convert type 'System.Web.UI.WebControls.TextBox' to 'bool'..Please Help me.How to correct this error