This　paper　explores　a　cooperative　practical　output　regulation　problem　for　a　class　of　heterogeneous　multiagent　nonlinear　systems　by　event-based　output　feedback.　Specifically,　we　shall　restrict　our　attention　to　the　situation　of　sampled-data-based　local　measurements.　As　usual,　due　to　agents　heterogeneity,　we　first　convert　the　problem　into　a　stabilization　one　for　the　so-called　augmented　system,　composed　of　the　agent　systems　and　suitably　designed　continuous-time　internal　models.　Then,　we　show　that　this　stabilization　can　be　solved　by　measurement　feedback.　It　finally　allows　us　to　establish　a　valid　event-based　protocol,　leading　to　a　global　practical　stability　property　and　meanwhile　guaranteeing　Zeno-free　condition.