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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...hese are the same
b = new Array(), // a and b are arrays with length 0
c = ['foo', 'bar'], // these are the same
d = new Array('foo', 'bar'), // c and d are arrays with 2 strings
// these are different:
e = [3] // e.length == 1, e[0] == 3
f = new Ar...
JavaScript checking for null vs. undefined and difference between == and ===
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+50
How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see not...
How to access property of anonymous type in C#?
...
answered Jul 29 '09 at 22:50
Greg BeechGreg Beech
119k3939 gold badges198198 silver badges238238 bronze badges
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Elastic search, multiple indexes vs one index and types for different data sets?
...
190
There are different implications to both approaches.
Assuming you are using Elasticsearch's de...
Convert between UIImage and Base64 string
...ta format
let imageData:NSData = NSData.init(contentsOfURL: url)!
Swift 2.0 > Encoding
let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
Swift 2.0 > Decoding
let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64Dec...
Lock, mutex, semaphore… what's the difference?
...|
edited Jan 29 '19 at 7:40
answered Feb 25 '10 at 9:21
Pet...
How to set date format in HTML date input tag?
...ify that as a short date, the first day of August this year should be 1/8-2016, but even Chrome and Opera show 01/08/2016. Other browsers, like Safari and Firefox (at least on OS X) ignore OS settings entirely and always show 2016-08-16 no matter what. On a site where users can set their own date pr...
Why does Unicorn need to be deployed together with Nginx?
...|
edited Nov 16 '15 at 22:05
Pete - MSFT
3,8991818 silver badges3737 bronze badges
answered Jan 5 '12 at...
CHECK constraint in MySQL is not working
...
MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
The CHECK...
How to get a variable value if variable name is stored as string?
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answered Dec 17 '09 at 12:09
Phil RossPhil Ross
22.5k99 gold badges6666 silver badges7474 bronze badges
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