How to set a Javascript object values dynamically?

问题

It's difficult to explain the case by words, let me give an example:

var myObj = {
    'name': 'Umut',
    'age' : 34
};

var prop = 'name';
var value = 'Onur';

myObj[name] = value; // This does not work

eval('myObj.' + name) = value;   //Bad coding ;)

How can I set a variable property with variable value in a JavaScript object?

回答1:

myObj[prop] = value;

That should work. You mixed up the name of the variable and its value. But indexing an object with strings to get at its properties works fine in JavaScript.

回答2:

myObj.name=value

myObj['name']=value     (Quotes are required)

Both of these are interchangeable.

Edit: I'm guessing you meant myObj[prop] = value, instead of myObj[name] = value. Second syntax works fine: http://jsfiddle.net/waitinforatrain/dNjvb/1/

回答3:

You can get the property the same way as you set it.

foo = {
 bar: "value"
}

You set the value foo["bar"] = "baz";

To get the value foo["bar"]

will return "baz".

回答4:

You could also create something that would be similar to a value object (vo);

SomeModelClassNameVO.js;

function SomeModelClassNameVO(name,id) {
    this.name = name;
    this.id = id;
}

Than you can just do;

   var someModelClassNameVO = new someModelClassNameVO('name',1);
   console.log(someModelClassNameVO.name);

回答5:

When you create an object myObj as you have, think of it more like a dictionary. In this case, it has two keys, name, and age.

You can access these dictionaries in two ways:

Like an array (e.g. myObj[name]); or
Like a property (e.g. myObj.name); do note that some properties are reserved, so the first method is preferred.

You should be able to access it as a property without any problems. However, to access it as an array, you'll need to treat the key like a string.

myObj["name"]

Otherwise, javascript will assume that name is a variable, and since you haven't created a variable called name, it won't be able to access the key you're expecting.

回答6:

simple as this myObj.name = value;

来源：https://stackoverflow.com/questions/36418463/mongoose-update-on-a-string-variable-not-working

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javascript

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properties

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