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Check if a value is an object in JavaScript
...o examine variable's properties, but it is not a bulletproof recipe (after all there's no recipe at all!) for checking whether it's an object, far from it. Since people tend to look for something to copy from here without doing any research, I'd highly recommend that they turn to the other, most upv...
indexOf method in an object array?
... think to see the performance of this method vs. a simple for loop. Especially when you're running on a mobile platform with limited resources.
– Doug
Aug 17 '15 at 5:51
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How to concatenate strings in twig
...like Alessandro said, and here it is in the documentation:
~: Converts all operands into strings and concatenates them. {{ "Hello
" ~ name ~ "!" }} would return (assuming name is 'John') Hello John!. – http://twig.sensiolabs.org/doc/templates.html#other-operators
And here is an example so...
Entity Framework 6 Code first Default value
...
You can do it by manually edit code first migration:
public override void Up()
{
AddColumn("dbo.Events", "Active", c => c.Boolean(nullable: false, defaultValue: true));
}
...
How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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Shell脚本编程30分钟入门 - 更多技术 - 清泛网 - 专注C/C++及内核技术
Shell脚本编程30分钟入门linux_shell_30min_guides什么是Shell脚本示例看个例子吧：#! bin shcd ~mkdir shell_tutcd shell_tutfor ((i=0; i<10; i++)); do touch test_$i.txt...
什么是Shell脚本
示例
看个例子吧：
#!/bin/sh
cd ~
mkdir shell_tut
cd shell_tut
for (...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...here are a couple of differences, though in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1...
How to check if a Unix .tar.gz file is a valid file without uncompressing?
...
What about just getting a listing of the tarball and throw away the output, rather than decompressing the file?
tar -tzf my_tar.tar.gz >/dev/null
Edited as per comment. Thanks zrajm!
Edit as per comment. Thanks Frozen Flame! This test in no way implies integrity ...
Using backticks around field names
...
To me it makes a lot of sense to use them at all times when dealing with field names.
Firstly, once you get into the habit, it doesn't hurt to just hit the backtick key.
Secondly, to me, it makes it easier to see what exactly are the fields in your query, and what ar...
Is there a way to programmatically scroll a scroll view to a specific edit text?
...way to scroll to an EditText object (or any other view object) programmatically?
22 Answers
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