Javascript 分配操作是否总是从右向左复制数据？

看看下面的Javascript代码：

var myString = new String();
myString.myObject = "myObject...";

//works fine as it shows "myObject..."
console.log("myString.myObject        :" + myString.myObject);
//OK myObject is also a string so it should give length and it works fine
console.log("myString.myObject.length :" + myString.myObject.length);
//it should not give anything or undefined since nothing is given to myString
console.log("myString                 :" + myString);
//myString is not yet defined so it should give undefined or 0..
console.log("myString.length          :" + myString.length);

//lets make a simple assignment
myString = myString.myObject;
//it should just copy value of myObject to myString so there are two copies of string "myObject.."

//lets log all the data all the data as i did above

console.log("myString.myObject        :" + myString.myObject);

//and this part is giving error
//console.log("myString.myObject.length :" + myString.myObject.length);

console.log("myString                 :" + myString);
console.log("myString.length          :" + myString.length);

在前半部分（作业前），它的工作方式和我预期的一样，但在作业后，它给出了一个错误

赋值后，

myString.myObject

似乎被删除了。是吗

当我试图访问

myString.myObject

时，控制台出现红色错误。作业是否删除了myString.myObject，或者这里发生了其他事情？

当您这样做时

myString = myString.myObject;

您正在用其

myObject

属性值替换整个

myString

值。由于它本身没有

myObject

属性，因此赋值后在

myString

中没有属性

在此赋值之后，执行此操作时，

myString

的值为

“myObject…”

myString = myString.myObject;

您正在用其

myObject

属性值替换整个

myString

值。由于它本身没有

myObject

属性，因此赋值后在

myString

中没有属性

在此赋值之后，

myString

的值是

“myObject…”