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How can I check a C# variable is an empty string “” or null? [duplicate]
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@Lion Liu: Actually I think PHP has exactly as much to offer. See: php.net/manual/en/function.empty.php
– Milan
Feb 2 '16 at 20:09
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Perform .join on value in array of objects
...Array.prototype.map is what you're looking for if you want to code functionally.
[
{name: "Joe", age: 22},
{name: "Kevin", age: 24},
{name: "Peter", age: 21}
].map(function(elem){
return elem.name;
}).join(",");
In modern JavaScript:
[
{name: "Joe", age: 22},
{name: "Kevin", age: 2...
Why are dates calculated from January 1st, 1970?
...1st, 1970) as default standard
The Question makes two false assumptions:
All time-tracking in computing is done as a count-since-1970.
Such tracking is standard.
Two Dozen Epochs
Time in computing is not always tracked from the beginning of 1970 UTC. While that epoch reference is popular, various...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...languages or characters.
On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.
Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci
utf8mb4_unicode_ci, which uses the Unicode r...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUsers(
IN rUsername VARCHAR(24),
IN rProductID INT UNSIGNED,
IN rPerm VARCHAR(16...
counting number of directories in a specific directory
... can instead test the directory's children and do not descend into them at all:
$ find .vim/* -maxdepth 0 -type d
.vim/after
.vim/autoload
.vim/bundle
.vim/colors
.vim/compiler
.vim/doc
.vim/ftdetect
.vim/ftplugin
.vim/indent
.vim/plugin
.vim/syntax
$ find .vim/* -maxdepth 0 -type d | wc -l
11
$ f...
一个科技公司只是碰巧卖起了披萨？ - 资讯 - 清泛网 - 专注C/C++及内核技术
...擎。无论达美乐将来想去卖汉堡还是卖卷饼，貌似都不成问题。
善用社交媒体进行病毒传播
达美乐不仅用科技手段在提升用户订餐体验上受益匪浅，更在消费最活跃的社交媒体上给自己铺了一条金光大道：它经常在社交媒体...
Nginx no-www to www and www to no-www
...n.php last;
# etc etc...
}
}
Note: I have not originally included https:// in my solution since we use loadbalancers and our https:// server is a high-traffic SSL payment server: we do not mix https:// and http://.
To check the nginx version, use nginx -v.
Strip www from ...
How do I force a favicon refresh?
I have a Grails application running locally using its own tomcat and I have just changed the favicon for a new one. Problem is that I can not see it in any browser. The old favicon shows up or I get no favicon at all, but not my new one. I do not think this is a Grails issue per se, more an issue...
Get the first N elements of an array?
...
Use array_slice()
This is an example from the PHP manual: array_slice
$input = array("a", "b", "c", "d", "e");
$output = array_slice($input, 0, 3); // returns "a", "b", and "c"
There is only a small issue
If the array indices are meaningful to you, remember that ar...