確保陣列中的所有值都在另一個陣列中

Question

我希望檢查event中的所有值都包含在state中。是這樣的函數應該返回true，否則爲false。這樣做的好方法是什麼？

const state = [1,2,4,5,6,7] 
const event = [1,2] 
if(state.contains(event))(} 

Answer 1

您可以使用every()和includes()陣列方法：

const state = [1, 2, 4, 5, 6, 7]; 
 
const event = [1, 2]; 
 
console.log(event.every(x => state.includes(x)));

Answer 2

確定是否一個事件包含的數據不存儲在狀態：

 let state = [1,2,3,5,6,7,8,9]; 
 
     
 
     let event = [1,2,3]; 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [] 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [4] 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [1,2,4] 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     state = []; 
 

 
     event = [1,2,3]; 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [] 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [4] 
 
     console.log(event.some(a=>!state.includes(a))); 
 

 
     event = [1,2,4] 
 
     console.log(event.some(a=>!state.includes(a)));