有谁知道如何合并两个对象

function assign(target: Record<string, Object>, ...source: Object[]): Record<string, Object> { 
  for (const items of source) { 
    for (const key of Object.keys(items)) { 
      target[key] = Reflect.get(items, key) 
    } 
  } 
  return target; 
}

interface IMergeSub { 
  testString: string, 
  testObject?: IMergeSub, 
  testArray?: Array<number> 
} 
 
interface IMerge { 
  a: IMergeSub, 
  b: IMergeSub[], 
  c: string[], 
  d: number 
} 
 
export function testAssign() { 
  let objectOne: IMerge = 
    { 
      a: { 
        testString: 'objectOne-a-testString', 
        testObject: { 
          testString: 'objectOne-a-testObject-testString' 
        }, 
        testArray: [1] 
      }, 
      b: [{ 
        testString: 'objectOne-b-testString', 
        testObject: { 
          testString: 'objectOne-b-testObject-testString' 
        }, 
        testArray: [2] 
      }], 
      c: ['objectOne-c'], 
      d: 3 
    } 
 
  let objectTwo: Record<string, Object> = { 
    'a': 'objectTwo-a', 
    'c': ['objectTwo-c'], 
    'e': 1 
  } 
 
  let objectThree: Record<string, Object> = { 
    'f': ['objectThree-f'] 
  } 
 
  // 合并多个对象，ObjectOne和ObjectTwo的属性都将附加到ObjectThree上，属性名相同时入参下标靠后的对象属性覆盖前面的对象属性 
  const multiObjectMerged = assign(objectThree, objectTwo, objectOne); 
  console.log('multiObjectMerged is:' + JSON.stringify(multiObjectMerged)); 
  console.log('objectThree is:' + JSON.stringify(objectThree)); 
 
  // 合并ObjectOne的属性到ObjectTwo，ObjectTwo的值会改变，属性名称相同时ObjectOne会覆盖ObjectTwo的属性 
  const objectMerged = assign(objectTwo, objectOne); 
  console.log('objectTwo is:' + JSON.stringify(objectTwo)); 
  console.log('objectMerged is:' + JSON.stringify(objectMerged)); 
}