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Better way to check variable for null or empty string?
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// Function for basic field validation (present and neither empty nor only white space
function IsNullOrEmptyString($str){
return (!isset($str) || trim($str) === '');
}
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Why can I throw null in Java? [duplicate]
...erException.
In other words, throw checks that its argument is nonnull, and if it is null, it throws a NullPointerException.
JLS 14.18 specifies this behavior:
If evaluation of the Expression completes normally, producing a null value, then an instance V' of class NullPointerException is cre...
How can I match multiple occurrences with a regex in JavaScript similar to PHP's preg_match_all()?
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I would suggest an alternative regex, using sub-groups to capture name and value of the parameters individually and re.exec():
function getUrlParams(url) {
var re = /(?:\?|&(?:amp;)?)([^=&#]+)(?:=?([^&#]*))/g,
match, params = {},
decode = function (s) {return decodeURI...
In log4j, does checking isDebugEnabled before logging improve performance?
...e when it involves invocation of the toString() methods of various objects and concatenating the results.
In the given example, the log message is a constant string, so letting the logger discard it is just as efficient as checking whether the logger is enabled, and it lowers the complexity of the ...
Reset select2 value and show placeholder
...t by select2. In my example If locations or grade select boxes are clicked and my select2 has a value than the value of select2 should reset and show the default placeholder. This script is resetting the value but won't show the placeholder
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How do I change the text of a span element using JavaScript?
...y, which means that a lot of people have probably taken over this solution and might have introduced unnecessary xss leaks. Could you consider updating your answer to use textContent instead, such that new people will be encouraged to use proper and secure methods?
– Tiddo
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How to include a quote in a raw Python string
...oted strings in your string (an extremely unlikely case), you can't do it, and you'll have to use non-raw strings with escapes.
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Update MongoDB field using value of another field
...ion 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 also introduced the $set pipeline stage operator which is an...
MySQL integer field is returned as string in PHP
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I just did some tests on Windows with Laravel and Mysql on the very same schema and database server. On Windows the primary key is returned as an Integer and on Linux it's a String.
– AturSams
Oct 28 '14 at 15:38
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How do I set up a simple delegate to communicate between two view controllers?
I have two UITableViewControllers and need to pass the value from the child view controller to the parent using a delegate. I know what delegates are and just wanted to see a simple to follow example.
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