Accessing Javascript Object with Key

Question

I have the following object self.originalData on the console:

enter image description here

However, when I try to access to first object in the array of originalData,

self.originalData[0hcMSJXljH]

getting the following error

the Uncaught>Syntax Error: Unexpected token ILLEGAL

I could not able to figure out where I am doing wrong.

Enclose the index in quotes if you're directly accessing it. — meder omuraliev, May 12 '15 at 19:43
Very closely related, but coming at it from the other side: [Dynamically access object property using variable](http://stackoverflow.com/questions/4244896/dynamically-access-object-property-using-variable) — apsillers, May 12 '15 at 19:47

jfriend00 · Accepted Answer · 2015-05-12T19:45:43.033

You can use:

self.originalData["0hcMSJXljH"]

instead. Object keys are strings so if you use the [] notation, then you have to put a string or a variable that contains a string inside the brackets.

Your particular case is a bit unusual because usually, you can use the dot notation as in obj.property, but because your key starts with a number, it is not a legal identifier to use with the dot notation (you can't do self.originalData.0hcMSJXljH). So, you are forced to use the bracket notation with that particular key.

score 2 · Answer 2 · answered May 12 '15 at 19:43

2

Try putting the key in quotes like this:

self.originalData['0hcMSJXljH']

answered May 12 '15 at 19:43

mnickell

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moonknight · Answer 3 · 2015-05-12T19:48:57.057

1

Have you tried

self.originalData["0hcMSJXljH"];

?

~~Otherwise:~~

self.originalData.0hcMSJXljH;

EDIT: last one not possible because the first char is a number, as explained to me

edited May 12 '15 at 19:48

answered May 12 '15 at 19:43

moonknight

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2

You can't do the second one. Identifiers used with the dot notation in Javascript cannot start with a number. – jfriend00 May 12 '15 at 19:47
Yep, I noticed from your answers, my bad – moonknight May 12 '15 at 19:48

marsh · Answer 4 · 2015-05-12T19:52:45.603

1

You must use quotes:

self.originalData['0hcMSJXljH']

edited May 12 '15 at 19:52

answered May 12 '15 at 19:44

marsh

1,431
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score 1 · Answer 5 · answered May 12 '15 at 19:45

You don't use quotes in your key, so it seems you are trying to use the variable identified by 0hcMSJXljH as the key. However, 0hcMSJXljH isn't a valid variable identifier, because it begins with a number, so your get an illegal-character error.

Simply use a string, not an identifier:

self.originalData["0hcMSJXljH"]

Accessing Javascript Object with Key

5 Answers5