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var foo = "bar" var bar = "realvalue"; Is it possible to print the value of bar using foo ?
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After a value is assigned to a variable using the assignment operator, you can assign the value of that variable to another variable using the assignment operator. var myVar; myVar = 5; var myNum; myNum = myVar; The above declares a myVar variable with no value, then assigns it the value 5 .
Command Window — To view the value of a variable in the Command Window, type the variable name. For the example, to see the value of a variable n , type n and press Enter. The Command Window displays the variable name and its value.
Here is some code: window. onload = function show(){ var x = 3; } function trig(){ alert(x); } trig();
Python will joyfully accept a variable by that name, but it requires that any variable being used must already be assigned. The act of assignment to a variable allocates the name and space for the variable to contain a value. We saw that we can assign a variable a numeric value as well as a string (text) value.
Approach 1: global variable
var foo = "bar"; var bar = "realvalue"; alert(window[foo]); OR
Approach 2: namespace
Divide your js to namespaces
var namespace = { foo : "bar", bar : "realvalue" }; alert(namespace[namespace.foo]); Yeah you can do something like this with eval
var foo = "bar"; var bar = "realvalue"; alert(eval(foo)); EDIT: Seems a lot of people are against using the eval() function. My advice before using it is read this question: Why is using the JavaScript eval function a bad idea?
Then once you understand the risks you can decide for yourself if you wish to use it.
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