JS object undefined problem

Question

<script type="text/javascript">
var X = {
   a: [{name:john, phone:777},{name:john, phone:777},{name:john, phone:777}],
   b: [{name:john, phone:777},{name:john, phone:777},{name:john, phone:777}],
   c: [{name:john, phone:777},{name:john, phone:777},{name:john, phone:777}],
   d: [{name:john, phone:777},{name:john, phone:777},{name:john, phone:777}]


}

var str = JSON.stringify(X);
alert(str);


</script>

What's wrong with this object?? It alerts "Uncaught ReferenceError: john is not defined" How come??

john needs to be in quotes as it is a string not a variable identifier — meouw
– meouw, Commented May 11, 2011 at 12:12
@meouw You should have made that an answer instead of a comment+1 — user657496
– user657496, Commented May 11, 2011 at 12:14

McStretch · Accepted Answer · 2011-05-11 12:19:58Z

8

You need quotes around john. Otherwise it is referring to an variable/object that has not been created:

var X = {
  a: [{name:"john", phone:777},{name:"john", phone:777},{name:"john", phone:777}]
...

Your code would be valid if john was previously defined:

var john = "john";
var X = {
  a: [{name:john, phone:777},{name:john, phone:777},{name:john, phone:777}]
  ...

Now john is a variable representing the string "john", and the JSON is valid.

edited May 11, 2011 at 12:19

answered May 11, 2011 at 12:13

McStretch

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Comments

kapa · Accepted Answer · 2011-05-11 12:13:18Z

5

Try name: 'john', you want it to be a string.

If you simply write john, it will be interpreted as a lookup for a variable (including possibly a function) named john. Since it finds no variable with that name, it will say it is not defined.

Same will go with phone, if the value can be something like 123-456-78 (would be interpreted as 123 minus 456 minus 78). If there can be only numbers, your solution is fine as it is now, otherwise use '123-456-78'.

answered May 11, 2011 at 12:13

kapa

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Comments

kapa · Accepted Answer · 2011-05-11 12:18:49Z

0

Change X like below. The object attribute names should be single or double quoted. String value should be quoted as well.

var X = {
   a: [{"name":"john", "phone":777},{"name":"john", "phone":777},{"name":"john", "phone":777}],
...
};

edited May 11, 2011 at 12:18

kapa

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answered May 11, 2011 at 12:18

jswidget

1

1 Comment

kapa Over a year ago

Object properties can be both notated as plain characters and as strings. - from Javascript Garden. So name: 'john' is perfectly right.

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