如何在 java 腳本對象中執行過濾？

Question

如何根據條件過濾 javascript 對象？

I tried this, but still it fills the remaining index of the object as null, I don't want the part of object if it doesn't meet my condition,here the condition is only if the index of the object is less the selectedIndex （這是我程序中的一些值）應該選擇它，其余的不是必需的

console.log(Object.keys(registrationData).map((val,ind)=>{
            return (ind<=selectedIndex ) ? registrationData[val] :null
   }));

Answer 1

嘗試這個

Object
  .values(registrationData)
  .filter((value, index) => index <= selectedIndex)