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How can I determine if a variable is 'undefined' or 'null'?
...ame) {
will evaluate to true if value is not:
null
undefined
NaN
empty string ("")
0
false
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Storing sex (gender) in database
... space savings, it only pays off if you have multiple bit fields.
Second, strings/chars have a "magic value" feel to them, regardless of how obvious they may seem at design time. Not to mention, it lets people store just about any value they would not necessarily map to anything obvious.
Third, a ...
Get Image size WITHOUT loading image into memory
...
As the comments allude, PIL does not load the image into memory when calling .open. Looking at the docs of PIL 1.1.7, the docstring for .open says:
def open(fp, mode="r"):
"Open an image file, without loading the raster data"
There ar...
How to pass a class type as a function parameter
... the types in the method call:
class func invokeService<T>(service: String, withParams params: Dictionary<String, String>, returningClass: T.Type, completionHandler handler: ((T) -> ())) {
// The compiler correctly infers that T is the class of the instances of returningClass
...
Get and Set a Single Cookie with Node.js HTTP Server
...eCookies() using:
RegExp.prototype.exec - use regex to parse "name=value" strings
Here's the working example:
let http = require('http');
function parseCookies(str) {
let rx = /([^;=\s]*)=([^;]*)/g;
let obj = { };
for ( let m ; m = rx.exec(str) ; )
obj[ m[1] ] = decodeURIComponent( m[2]...
What happens if i return before the end of using statement? Will the dispose be called?
...cked (where types differ):
using (SqlConnection conn = new SqlConnection("string"))
using (SqlCommand comm = new SqlCommand("", conn))
{
}
And also comma-delimited (where types are the same):
using (SqlCommand comm = new SqlCommand("", conn),
SqlCommand comm2 = new SqlCommand("", conn))...
UIBarButtonItem with custom image and no border
...ation code here
}
@end
So anywhere in your code you can create bar item calling this method (provided that you include a header with its declaration).
P.S. You do not need to use 'v' UIView as you can create UIBarButtonItem with a button as custom view directly.
P.P.S. You also need [forward rel...
How could I use requests in asyncio?
I want to do parallel http request tasks in asyncio , but I find that python-requests would block the event loop of asyncio . I've found aiohttp but it couldn't provide the service of http request using a http proxy.
...
CodeIgniter: Create new helper?
...o it.
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
if ( ! function_exists('test_method'))
{
function test_method($var = '')
{
return $var;
}
}
Save this to application/helpers/ . We shall call it "new_helper.php"
The first line exists to ...
Stopping scripters from slamming your website
... I don't quite understand the "spinner" concept. Is this just an extra piece of data that is placed inside an html <form> and sent upon submission? Because a bot can easily scrape that as well.
– Ponkadoodle
Sep 6 '13 at 19:22
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