## VUE3 ``` setup() { const firstName = ref("Kobe"); const lastName = ref("Bryant"); // 1.用法一: 傳入一個getter函數 // computed的返回值是一個ref對象 const fullName = computed(() => firstName.value + " " + lastName.value); // 2.用法二: 傳入一個對象, 對象包含getter/setter const fullName = computed({ get: () => firstName.value + " " + lastName.value, set(newValue) { const names = newValue.split(" "); firstName.value = names[0]; lastName.value = names[1]; } }); const changeName = () => { // firstName.value = "James" fullName.value = "coder why"; } return { fullName, changeName } } ```