How should I create a changing variable as a global variable?
so something like:
function globVar(variable){
window.variable;
}
So in this way I could create global variables in an automatic mode too, and also I could create them for myself easier :)
EDIT
For example I could create a global variable just like this: globVar('myVariable'); then myVariable is added to the global variables.
Sorry to say this, but the answers you have received are bad habits that you should stay away from. A better programming practice, and perhaps the proper programming practice, would be to pseudo-namespace your global variables so to not clutter the Global namespace/scope. The reasoning behind this is to make your code more manageable, and more importantly, make life easier for you if/when your application becomes large. A simple mechanism to define a namespace is to use the module-pattern made famous by Douglas Crockford.
Here's a simple example:
var myNamespace = function(){
var o = {};
var globals = {};
var setGlobVar = function(name, value) {
globals[name] = value;
};
var getGlobVar = function(name) {
if (globals.hasOwnProperty(name)) {
return globals[name];
} else {
// return null by default if the property does not exist
return null;
}
};
o.setGlobVar = setGlobVar;
o.getGlobVar = getGlobVar;
return o;
}();
To use this, you simply call it like methods of an object.
myNamespace.setGlobVar("secret_msg", "Dumbledore dies, so does Hedwig");
myNamespace.getGlobVar("secret_msg");
You could also expose the globals variable instead of using the setGlobVar and getGlobVar methods to use it, if you wanted to simplify how you access the variable.
The point is to stay away from defining variables in the global namespace (i.e., the window object) as much as possible, by creating a namespace of your own. This reduces the chance of name collisions, accidentally rewrites or overrides, and again, global namespace clutter.
An even simpler approach to doing this is to simply define an object and augment its properties.
var globals = {};
globals.SECRET_MSG = "Snape is not a traitor"
Though I would extend this approach by wrapping globals into a namespace that is specific to my application.
var myNamespace = {};
myNamespace.globals = {};
myNamespace.globals.SECRET_MSG = "Snape is not a traitor"
NOTE: This is actually the same as original module-pattern approach I suggested, just without the get and set accessor methods and coded differently.
window to create a global variable you say that I should add it to another variable? so for example, globalVars.variable?
window object) by creating your own namespace. The method I proposed above may be overkill for what you need, but it is worth learning if you plan on doing any Javascript development.
Call the function as globVar('myVar','myVarValue')
function globVar(variable,value){
window[variable] = value;
}
Here is a jsfiddle: http://jsfiddle.net/emQQm/
window[variable] = value and be done with it?alert(myVar); which is good if I know the name of the variable what was created, and another problem is that I don't know how to call it because If I want to call it with a variable (for example alert(variable)) what calls the global variables value because variable is reserved inside the function.. oh this is a bit complicated :))
window.variable = variable;
Don't understand what is an "automatic mode", so this might not what you wanted.
globVar('myVariable'); then myVariable is added to the global variables.
window.variable = 123;, you assign a value that you are going to use from now on.window.variablesFromUsers = {};. Then your users can do something like: window.variablesFromUsers['abc'] = 123; and you will be able to get it in the same way: window.variablesFromUsers['abc'] will give you 123. If you want to get all the variables set by users, you can do: for v in window.variablesFromUsers and in the loop get all the names ('abc' in the previous example), then do window.variablesFromUsers[o] to get the contents (123 in the example). Hope this helps.
null. :)