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UnboundLocalError on local variable when reassigned after first use
... assign values to them from inside or outside the function. If a variable is assigned within a function, it is treated by default as a local variable. Therefore, when you uncomment the line you are trying to reference the local variable c before any value has been assigned to it.
If you want the ...
What is the size of ActionBar in pixels?
...actionBarSize
or if you're an ActionBarSherlock or AppCompat user, use this
?attr/actionBarSize
If you need this value at runtime, use this
final TypedArray styledAttributes = getContext().getTheme().obtainStyledAttributes(
new int[] { android.R.attr.actionBarSize });
mActi...
Why can't I initialize non-const static member or static array in class?
...nstant integral or enumeration types to be initialized inside the class. This is the reason a is allowed to be initialized while others are not.
Reference:
C++03 9.4.2 Static data members
§4
If a static data member is of const integral or const enumeration type, its declaration in the class de...
What's the difference between isset() and array_key_exists()? [duplicate]
...
array_key_exists will definitely tell you if a key exists in an array, whereas isset will only return true if the key/variable exists and is not null.
$a = array('key1' => 'フーバー', 'key2' => null);
isset($a['key1']); ...
Is it possible to ping a server from Javascript?
...
I have found someone that accomplishes this with a very clever usage of the native Image object.
From their source, this is the main function (it has dependences on other parts of the source but you get the idea).
function Pinger_ping(ip, callback) {
i...
how to implement a pop up dialog box in iOS
After a calculation, I want to display a pop up or alert box conveying a message to the user. Does anyone know where I can find more information about this?
...
jQuery see if any or no checkboxes are selected
I know how to see if an individual checkbox is selected or not.
8 Answers
8
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What's the difference between ASCII and Unicode?
...h not all numbers are currently assigned, and some are reserved).
Unicode is a superset of ASCII, and the numbers 0–127 have the same meaning in ASCII as they have in Unicode. For example, the number 65 means "Latin capital 'A'".
Because Unicode characters don't generally fit into one 8-bit byte...
Check if character is number?
...
You could use comparison operators to see if it is in the range of digit characters:
var c = justPrices[i].substr(commapos+2,1);
if (c >= '0' && c <= '9') {
// it is a number
} else {
// it isn't
}
...
Protect .NET code from reverse engineering?
Obfuscation is one way, but it can't protect from breaking the piracy protection security of the application. How do I make sure that the application is not tampered with, and how do I make sure that the registration mechanism can't be reverse engineered?
...