React把数组转为对象

react 数组 const arr1= [
{“id”:”1”,”key_name”:”a”,”key_value”:”aaa”},
{“id”:”2”,”key_name”:”b”,”key_value”:”bbb”},
{“id”:”3”,”key_name”:”c”,”key_value”:”ccc”},
{“id”:”3”,”key_name”:”d”,”key_value”:”ddd”},

];
要为转为 对象 obj ={“a”:”aaa”,
“b”:”bbb”,
“c”:”ccc”,
“d”:”ddd”}

请问哪位高手知道要怎么转换？

var obj = {}
for(var i=0;i obj[arr1[i].key_name] = arr1[i].key_value
}
console.log(obj)

let arr = arr1.map(item => {
let obj = {};
obj[item.key_name] = item.key_value;
return obj;
})