Get property of object in JavaScript
Basically I have a form with a <select>
that chooses which set of data to use (values are "m", "f" and "c"). I then have a dictionary/object with the data in:
var gdas = {
// Male
"m": {
开发者_开发知识库 "calories": 2500,
"protein": 55,
"carbohydrates": 300,
"sugars": 120,
"fat": 95,
"saturates": 30,
"fibre": 24,
"salt": 6
},
// Female
"f": {
"calories": 2000,
// etc.
};
Now I need to get gdas.m
/gdas.f
/gdas.c
but I'm not sure what syntax to use - I've tried:
var mode = $("#mode").val();
var gda_set = gdas.mode;
var gda_set = gdas[mode];
What's the right syntax/method for this?
Since you're referencing the property via a variable, you need the bracket notation.
var gda_set = gdas[mode];
...which is the same notation you would use if you were passing a String.
var gda_set = gdas["f"];
You don't have "mode" attribute in that variable. You must use if's to detect which sex you are processing and get gdas.m.fibre
or gdas.f.salt
.
You can use gdas[mode], it selects the element that is indexed by the value of mode.
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