Javascript 使用变量作为对象名

Is it a global variable? If so, these are actually part of the window object, so you can do window[objname].value.

If it's local to a function, I don't think there's a good way to do what you want.

You can't do this in general, except at the window scope, where you can write window[objname].value = 'value';

Global:

myObject = { value: 0 };
anObjectName = "myObject";
this[anObjectName].value++;


console.log(this[anObjectName]);

Global: v2

var anObjectName = "myObject";
this[anObjectName] = "myvalue"


console.log(myObject)

Local: v1

(function() {
var scope = this;


if (scope != arguments.callee) {
arguments.callee.call(arguments.callee);
return false;
}


scope.myObject = { value: 0 };
scope.anObjectName = "myObject";
scope[scope.anObjectName].value++;


console.log(scope.myObject.value);
})();

Local: v2

(function() {
var scope = this;


scope.myObject = { value: 0 };
scope.anObjectName = "myObject";
scope[scope.anObjectName].value++;


console.log(scope.myObject.value);
}).call({});

You could use eval:

eval(variablename + ".value = 'value'");

The object exists in some scope, so you can almost always access the variable via this syntax:

var objname = "myobject";
containing_scope_reference[objname].some_property = 'some value';

The only place where this gets tricky is when you are in a closed scope and you want access to a top-level local variable. When you have something like this:

(function(){
var some_variable = {value: 25};
var x = "some_variable";
console.log(this[x], window[x]); // Doesn't work
})();

You can get around that by using eval instead to access the current scope chain ... but I don't recommend it unless you've done a lot of testing and you know that that's the best way to go about things.

(function(){
var some_variable = {value: 25};
var x = "some_variable";
eval(x).value = 42;
console.log(some_variable); // Works
})();

Your best bet is to have a reference to a name in an always-going-to-be-there object (like this in the global scope or a private top-level variable in a local scope) and put everything else in there.

Thus:

var my_outer_variable = {};
var outer_pointer = 'my_outer_variable';
// Reach my_outer_variable with this[outer_pointer]
// or window[outer_pointer]


(function(){
var my_inner_scope = {'my_inner_variable': {} };
var inner_pointer = 'my_inner_variable';
// Reach my_inner_variable by using
// my_inner_scope[inner_pointer]
})();

I think Shaz's answer for local variables is hard to understand, though it works for non-recursive functions. Here's another way that I think it's clearer (but it's still his idea, exact same behavior). It's also not accessing the local variables dynamically, just the property of the local variable.

Essentially, it's using a global variable (attached to the function object)

// Here's  a version of it that is more straight forward.
function doIt() {
doIt.objname = {};
var someObject = "objname";
doIt[someObject].value = "value";
console.log(doIt.objname);
})();

Which is essentially the same thing as creating a global to store the variable, so you can access it as a property. Creating a global to do this is such a hack.

Here's a cleaner hack that doesn't create global variables, it uses a local variable instead.

function doIt() {
var scope = {
MyProp: "Hello"
};
var name = "MyProp";
console.log(scope[name]);
}

See Javascript: interpret string as object reference?

When using the window[objname], please make sure the objname is global variables. Otherwise, will work sometime, and fail sometimes. window[objname].value.

If object is in some namespace ie. Company.Module.Components.Foo you can use this function:

CoffeeScript:

objByName: (name, context = window) ->
ns = name.split "."
func = context
for n, i in ns
func = func[n]
return func

Resulted Js:

objByName: function(name, context) {
var func, i, n, ns, _i, _len;
if (context == null) {
context = window;
}
ns = name.split(".");
func = context;
for (i = _i = 0, _len = ns.length; _i < _len; i = ++_i) {
n = ns[i];
func = func[n];
}
return func;
}

Then you can create a new object or do whatever. Note the parenthises through.

var o = new (objByName('Company.Module.Components.Foo'))
objByName('some.deeply.nested.object').value

This idea is borrowed from similar question: How to execute a JavaScript function when I have its name as a string

var micro=[{'test':'hello'}];


var device = 'test';


console.log(micro[device]);

Use square bracket around variable name.

var objname = 'myobject';
{[objname]}.value = 'value';

One of the challenges I had with the answers is that it assumed that the object was a single level. For example,

const testObj = { testKey: 'testValue' }
const refString = 'testKey';
const refObj = testObj[refString];

works fine, but

const testObj = { testKey:
{ level2Key: 'level2Value' }
}
const refString = 'testKey.level2Key';
const refObj = testObj[refString];

does not work.

What I ended up doing was building a function to access multi-level objects:

objVar(str) {
let obj = this;
const parts = str.split('.');
for (let p of parts) {
obj = obj[p];
}
return obj;
}

In the second scenario, then, I can pass the string to this function to get back the object I'm looking for:

const testObj = { testKey:
{ level2Key: 'level2Value' }
}
const refString = 'testObj.testKey.level2Key';
const refObj = objVar[refString];

You can set an objects property this way:

var obj = {};
obj.whateverVarName = 'yourVal';
console.log(obj);

If you already know the list of the possible varible names then try creating a new Object(iconObj) whose properties name are same as object names, Here in below example, iconLib variable will hold two string values , either 'ZondIcons' or 'MaterialIcons'. propertyName is the property of ZondIcons or MaterialsIcon object.

   const iconObj = {
ZondIcons,
MaterialIcons,
}
const objValue = iconObj[iconLib][propertyName]

let players = [];
players[something] = {};
players[something].somethingElse = 'test';
console.log(players);

-> [ something: { somethingElse: 'test' } ];

It can be as simple as this

var myObjKey = "key";


var obj = {[myObjKey] : "value" };
console.log(obj); // => {key: 'value'}