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Posts tagged with “as3” and “javascript”
Quick date validation with a Regular Expression
/(?:19|20)[0-9]{2}-(?:(?:0[1-9]|1[0-2])-(?:0[1-9]|1[0-9]|2[0-8])|(?:(?!02)(?:0[1-9]|1[0-2])-(?:29|30))|(?:(?:0[13578]|1[02])-31))/
Here's the breakdown of what it does:
Given a date format of YYYY-MM-DD (standard MySQL date format and easiest format for sorting) it makes sure that
- the year is numeric and starts with 20 or 19, and
- the month is numeric and is either
- between 01 - 12 and followed by a numeric day value between 01-28;
- between 01 - 12 but not 02 and followed by a day value of 29 or 30; or
- one of 01,03,05,07,08,10,12 and followed by a day value of 31
I have left out Feb. 29th so that you are forced to do a secondary leap year check.
Difference between using Object as associative array in Flash AS3 and JavaScript
As I was porting a Roman number converter (I will post it shortly) I had written in JavaScript to AS3 and ran into an interesting "quirk" of the AS3 Object class. I doesn't keep the keys in the same order that they were declared. The code used an Object literal as an associative array; holding each roman "digit" along with it's decimal equivalent in descending order by value. I'd then use a for ... in loop to cycle through the object. In JavaScript I'd get the values in the same order they had been generated. AS3 seems to be a little more cavalier. The following code in Javascript:
var o = {
"name1":1,
"name2":1,
"name3":1,
"name4":1,
"name5":1
};
var a=0;
for (var n in o) {
document.write(" o " + a + ":"+n);
a++;
}
produces this result in all major browsers (Firefox 3.5, IE 8, Safari 4, Opera 9.54, Chrome 2):
o 0:name1 o 1:name2
o 2:name3
o 3:name4
o 4:name5
However, using the following code in the Flash IDE
var o:Object = {
"name1":1,
"name2":1,
"name3":1,
"name4":1,
"name5":1
};
var a:uint = 0
for (var n:String in o) {
trace(" o " + a + ":"+n);
a++;
}
resulted in the following trace result:
o 0:name4
o 1:name5
o 2:name1
o 3:name2
o 4:name3
Oddly, it seemed to produce the exact same order each time I ran it. I tried it with a Dictionary, to see if the made a difference, but results were similar. I tried different values, to try and find a reason for the ordering -- to no avail. If someone knows why it's consistently picks the same random order, I'd love to know.