AS3 Call a variable from a compound string - actionscript-3

I don't know how to explain this good, I'll do my best :p
I have this code:
public function clickeado(MouseEvent):void{
if(getChildByName("placa") == null){
addChild(info);
}
trace(MouseEvent.target.name)
switch(MouseEvent.target.name){
case "_783":
info.circuito_tf.text = _783_circuito;
info.localidad_tf.text = _783_localidad;
info.responsable_tf.text = _783_responsable;
break;
I want that the text of "info.circuito_tf.text" to be the value of the variable called "_783_circuito". It's ok. Now I have 17 more cases, so I decided to do something like this:
switch(MouseEvent.target.name){
case "_783":
info.circuito_tf.text = MouseEvent.target.name + "_circuito";
info.localidad_tf.text = MouseEvent.target.name + "_localidad";
info.responsable_tf.text = MouseEvent.target.name + "_responsable";
break;
I wish I explained well, thanks!
ps: the value of info.circuito_tf.text in the second case it's "783circuito" instead of the value of the variable

You can address a variable through a string via this syntax:
info.circuito_tf.text = this[MouseEvent.target.name + "_circuito"];
Watch out for undefined values, though.
Yes, with this syntax you don't need the switch statement at all, just make sure your movie clips all have valid names and correct variables exist and are assigned values.

Related

AS3 Boolean seemingly not working

Ok, so this is obviously going to be something that I stupidly overlooked in my code, but I am having problems with a boolean check in as3. In the below if statement I set a boolean, I can confirm that the boolean is set in this if switch as I have run a trace to check that:
if(switchA && switchB){
if(Side == "LEFT"){
localAttachCoords.x = (-Parent.collision.SideLength - entity.collision.SideLength)/2
localAttachCoords.y = Parent.collision.SideLength/2 - (((TargNode-1)*8) + entity.collision.SideLength/2)
}
if(Side == "RIGHT"){
localAttachCoords.x = (Parent.collision.SideLength + entity.collision.SideLength)/2
localAttachCoords.y = -(Parent.collision.SideLength/2 - (((TargNode-1)*8) + entity.collision.SideLength/2))
}
if(Side == "UP"){
localAttachCoords.y = (Parent.collision.SideLength + entity.collision.SideLength)/2
localAttachCoords.x = -(Parent.collision.SideLength/2 - (((TargNode-1)*8) + entity.collision.SideLength/2))
}
if(Side == "DOWN"){
localAttachCoords.y = (-Parent.collision.SideLength - entity.collision.SideLength)/2
localAttachCoords.x = Parent.collision.SideLength/2 - (((TargNode-1)*8) + entity.collision.SideLength/2)
}
entity.attached = true
entity.Parent = Parent
}
This would all be well and good, but for the fact that in a function from another class, executed every frame, claims that the boolean was set to false, I confirmed this with another trace function.
This is the function, taken from the class whose instance is referred to as entity in the above switch:
public function update(){
if (physics) physics.update()
if (node && physics){
trace(attached)
if(attached){
physics.nodeUpdate()
}
}
}
This function claims in the trace that attached == false despite it being set true earlier with no other reference to the attached variable. Any help would be appreciated!
Pathing
There are some un-addressed variables in your issue, foremost being the pathing you're taking to check your variable. This is relevant because of namespaces/scope affect what each piece of code has access to.
If your functions and variables shared the same space (i.e., global/document/timeline), then any reference the the same named variable will always return the same value, unless (as LoremIpsum noted) it's being shadowed by a local variable by the same name.
Obviously, this is not the case since you're using public function which is a class-only declaration. If the boolean you're looking for is on the timeline, and the class wants to read that variable, you need to have a valid path to it. Instantiated classes that are DisplayObjects and have been added to the DisplayList have both parent and stage properties which you can use to access the timeline global namespace (thereby providing access to your boolean).
However, if the class is not a DisplayObject (e.g., it does not extend a Sprite, Shape, or MovieClip), then access to the timeline has to be provided manually, either by setting a property on the class, or passing an argument to a method on the class.
Further complicating the matter is if the Boolean exists in another class object (either instantiated or static), you'd then need a way to get between them. A case of A sees B, C sees B, but neither A or C see eachother.
Values
A boolean is always going to be false, even if the assigned value was null, so if your class is trying to reference a variable that it can't see, that value will always be false. For example...
var foo:Boolean = this["fiddlesticks"];
trace("foo = " + foo); // traces: "foo = false"
There is no property this.fiddlesticks, so while the resolved value is null, foo becomes false. Consider using hasOwnProperty(), which indicates whether an object has a specified property defined, and is a method available to all objects.
Switch
You don't have to manually create your own switch using if then else if, AS3 has its own switch statement.
switch (Side) {
case "LEFT":
// Do stuff for left
break;
case "RIGHT":
// Do stuff for right
break;
case "UP":
// Throw your hands up
break;
case "DOWN":
// Get down and boogie!
break;
}
I hope that all helps. I'd like to say exactly what's going on with the access to your Boolean, but there simply isn't enough information to say.
Cheers!

AS3 - getting variable named in order within a function

I am sorry if this is a beginner's question.
I made some Arrays named like map01, map02 and so on... As you can see, I'm making a tile-based flash here. And I need to make a function that when you input a number like: createmap(1); it will get the variable map01 and use the information.
Can I do anything like: var temp:Array = Array(["map" + valueInput]);??
Please tell me if you need anything more.
First, instead of having variables with indices in their names, you should create an array of them. Here, an array of arrays.
So you just have to call var temp:Array = maps[valueInput] as Array;.
If you really don't want to do that and stick with your n variables, you can write
var index:String = valueInput.toString();
if (index.length == 1)
index = "0" + index; //have the index on two digits "01", "02"
var temp:Array = this["map" + index];
Note that it will only work for your 99 first variables (oh God...)

LINQ-to-SQL oddity with multiple where clause arguments on the same field

My problem requires me to dynamically add where clauses to a IQueryable based on user input. The problem i'm having is that Linq-to-SQL doesn't seem to like having multiple where clauses on the same field, it actually duplicates the search arg value for the last item on all parameters. I verified this behavior through a SQL trace. Here is what I'm seeing.
WHERE ([t22].[OpenText] LIKE #p11) AND ([t22].[OpenText] LIKE #p12)
-- #p11: Input NVarChar (Size = 10; Prec = 0; Scale = 0) [%classify%] // Should be 2da57652-dcdf-4cc8-99db-436c15e5ef50
-- #p12: Input NVarChar (Size = 10; Prec = 0; Scale = 0) [%classify%]
My code uses a loop to dynamically add the where clauses as you can see below. My question is how do I work around this? This pretty much seems like a bug with the tool, no?
// add dyanmic where clauses based on user input.
MatchCollection searchTokens = Helper.ExtractTokensWithinBracePairs(filterText);
if (searchTokens.Count > 0)
{
foreach(Match searchToken in searchTokens)
query = query.Where((material => material.OpenText.Contains(searchToken.Value)));
}
else
{
query = query.Where((material => material.OpenText.Contains(filterText)));
}
Closing over the loop variable considered harmful! Change
foreach(Match searchToken in searchTokens) {
query = query.Where(
material => material.OpenText.Contains(searchToken.Value)
);
}
to
foreach(Match searchToken in searchTokens) {
Match token = searchToken;
query = query.Where(
material => material.OpenText.Contains(token.Value)
);
}
You are closing over the loop variable, which is considered harmful. To fix do this:
foreach(Match searchToken in searchTokens)
{
Match searchToken2 = searchToken;
// ^^^^^^^^^^^^ copy the value of the reference to a local variable.
query = query.Where(material => material.OpenText.Contains(searchToken2.Value));
// use the copy here ^^^^^^^^^^^^
}
The reason why your version doesn't work is that the query refers to the variable searchToken, not the value it had when the query was created. When the variable's value changes, all your queries see the new value.
I don't have enough rep to leave comments yet (or this would be a comment and not an answer) but the answers listed here worked for me.
However, I had to turn off compiler optimizations in order for it to work. If you do not turn off compiler optimizations (at least at the method level) then the compiler sees you setting a loop variable to a local variable and throws the local variable away.

action script 3.0 a string variable that should have only number

In action script var x:String="123abc" I have to check any character, for that string.
i.e. here "abc" is that string so I give an alert that this string should contain only numbers.
How can I do that?
Do you mean to say that you would like to dispatch an alert if a string contains letters
var testVar:String = '123abc';
var pattern:RegExp = /[a-zA-Z]/g;
if( testVar.search(pattern) == -1 )
{
//all good there's no letters in here
}
else
{
//Alert, alert, letter detected!
}
the "pattern" variable is a RegularExpression that's adaptable. Here I'm only checking for letters... If you need more control, get more info about RegularExpressions or come back here with the specific filter you'd like to implement.
I think you are looking for Regular Expression support in AS3.
If the user is inputting text via a TextField then you can set the restrict property to limit the characters that can be entered into the textfield:
textFieldInstance.restrict = "0-9";
TextField.restrict documentation:
http://livedocs.adobe.com/flex/3/langref/flash/text/TextField.html#restrict

AS3: How to simplify Action Script 3 Code?

Here's a example that I've to use when I want to create a button with mouse-over effect:
this.buttonExample.buttonMode = true;
this.buttonExample.useHandCursor = true;
this.buttonExample.addEventListener(MouseEvent.CLICK,myaction);
I'm new to AS3 - is there any way, to simplify this code like this:
this.buttonExample.buttonMode = true;.useHandCursor = true;.addEventListener(MouseEvent.CLICK,myaction);
why does it not works ?
Its already as simple as it gets. Firstly
this.buttonExample.buttonMode = true;
this.buttonExample.useHandCursor = true;
this.buttonExample.addEventListener(MouseEvent.CLICK,myaction)
is much more readable than
this.buttonExample.buttonMode = true;.useHandCursor = true;.addEventListener(MouseEvent.CLICK,myaction);
Always go for readbility over anything else. And secondly,
this.buttonExample.buttonMode = true;
does not return an object so you can't interact with anything.
If you're using that pattern a lot, you can make a helper function:
public function setAsButton(button:Sprite, clickHandler:Function):void {
button.buttonMode = button.userHandCursor = true;
button.addEventListener(MouseEvent.CLICK, clickHandler);
}
Then call it somewhere:
setAsButton(this.buttonExample, myaction);
If you feel that typing this.buttonExample over and over again is too repetitive, simply assign that object to a variable and use that variable in the rest of the statements:
var b : Button = this.buttonExample;
b.buttonMode = true;
b.useHandCursor = true;
b.addEventListener(...);
As other's have mentioned, there's also the with statement, but it's use is discouraged since it makes the code harder to read, and may lead to weird results:
with (this.buttonExample) {
buttonMode = true;
useHandCursor = true;
addEventListener(...);
}
You can, of course, combine these suggestions with other tricks, like chaining assignments:
var b : Button = this.buttonExample;
b.buttonMode = b.useHandCursor = true;
b.addEventListener(...);
Be very careful to only chain assignments in this way if the assigned value is immutable (e.g. true, false, numbers and strings, but not arrays or most other objects), because the same object will be assigned to all variables on the left side. If the value is immutable this doesn't matter, but if it's mutable you can end up with weird results, like this in this example:
a = b = [ ];
a.push(1);
b.push(2);
trace(a); // outputs 1, 2
trace(b); // also outputs 1, 2
The reason for this result is that a and b both reference the same array, and since arrays are mutable it doesn't matter how you access the object, it will still be changed. a and b don't reference different arrays just because they are different variables.
You may think that you could do something like the following, but it will not work.
// this will NOT work
var b : Button = this.buttonExample;
(b.buttonMode = b.useHandCursor = true).addEventListener(...);
The reason why it works to say b.buttonMode = b.useHandCursor = true, but not to add .addEventListener(...) is that the value of an assignment expression (e.g. b.buttonMode = true) is the value assigned to the left hand side (e.g. true). If you add .addEventListener(...) to that you are essentially saying true.addEventListener(...), which clearly is not what you want. In other words
b.buttonMode = b.useHandCursor = false;
is equivalent to
b.useHandCursor = false;
b.buttonMode = b.useHandCursor;
Which should hopefully also make the caveats mentioned above plain.
you can use the with statement. however I'd not encourage you to do so, since it leads to a lot of ambiguity and unclearness.
also, you can have multiple assignments:
this.buttonExample.buttonMode = this.buttonExample.useHandCursor = true;
this sometimes is useful, but for the sake of readability, you shouldn't overuse it.
greetz
back2dos