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Difference between if () { } and if () : endif;
Are there any differences between...
18 Answers
18
...
Does Go have “if x in” construct similar to Python?
Without iterating over the entire array, how can I check if x in array using Go? Does the language have a construct?
7 A...
What is the purpose of “&&” in a shell command?
...wo
the intent is to execute the command that follows the && only if the first command is successful. This is idiomatic of Posix shells, and not only found in Bash.
It intends to prevent the running of the second process if the first fails.
You may notice I've used the word "intent" - tha...
How can I convert String to Int?
...e to make decisions about the results of the parsing attempt:
int x = 0;
if (Int32.TryParse(TextBoxD1.Text, out x))
{
// you know that the parsing attempt
// was successful
}
If you are curious, the difference between Parse and TryParse is best summed up like this:
The TryParse metho...
Check Whether a User Exists
...n also check user by id command.
id -u name gives you the id of that user.
if the user doesn't exist, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as if already checks for the exit code. There's no ...
Check if application is on its first run [duplicate]
...verride
protected void onResume() {
super.onResume();
if (prefs.getBoolean("firstrun", true)) {
// Do first run stuff here then set 'firstrun' as false
// using the following line to edit/commit prefs
prefs.edit().putBoolean("firstrun", false)...
Get the first item from an iterable that matches a condition
...
In Python 2.6 or newer:
If you want StopIteration to be raised if no matching element is found:
next(x for x in the_iterable if x > 3)
If you want default_value (e.g. None) to be returned instead:
next((x for x in the_iterable if x > 3), d...
Procedure expects parameter which was not supplied
...
In addition to the other answers here, if you've forgotten to put:
cmd.CommandType = CommandType.StoredProcedure;
Then you will also get this error.
share
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i...
Do checkbox inputs only post data if they're checked?
...standard behaviour for browsers to only send the checkbox input value data if it is checked upon form submission?
12 Answer...
Permutations in JavaScript?
...
If you notice, the code actually splits the chars into an array prior to do any permutation, so you simply remove the join and split operation
var permArr = [],
usedChars = [];
function permute(input) {
var i, c...