<p>This paper is dedicated to investigating a generalized extended state observer issue for switched nonlinear systems with persistent dwell-time regularity. Firstly, for achieving reasonable information exchange scheduling and estimating lumped unmodeled dynamics and external disturbances, a sampled-data generalized extended state observer is established, in which the observer input is only transmitted and updated at sampling instants. Secondly, by constructing piecewise-continuous delay-dependent Lyapunov functional, the exponential convergence criterion and observer gain design method are presented. In the analysis, the sum of squares program is employed, reducing the linear matrix inequality constraints with infinite-dimensions to a finite number of sum of squares constraints. Finally, the merits of the proposal are demonstrated by a numerical example and an application example on the H-bridge rectifier system.</p>