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Objective-C ARC: strong vs retain and weak vs assign
...on error to use assign for an object. You have to use either weak or unsafe_unretained (which is unsafe, obviously) if you don't want to retain the property.
– cobbal
Jan 19 '12 at 15:07
...
Which method performs better: .Any() vs .Count() > 0?
...
EDIT: Here are generated SQLs. Beauties as you can see ;)
ANY:
exec sp_executesql N'SELECT TOP (1)
[Project2].[ContactId] AS [ContactId],
[Project2].[CompanyId] AS [CompanyId],
[Project2].[ContactName] AS [ContactName],
[Project2].[FullName] AS [FullName],
[Project2].[ContactStatusId] AS [...
Check if a JavaScript string is a URL
...{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
'(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
'(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
'(\\#[-a-z\\d_]*)?$','i'); // fragment locator
return !!pattern.test(str);
}
...
Use of #pragma in C
... == 7
Here's how you'd do the same thing in GCC:
struct PackedStructure __attribute__((__packed__))
{
char a;
int b;
short c;
};
// sizeof(PackedStructure == 7)
The GCC code is more portable, because if you want to compile that with a non-GCC compiler, all you have to do is
#define __att...
Most efficient way to determine if a Lua table is empty (contains no entries)?
... the context of lua 5.2 & 5.3, is that non locals are either upvals or _ENV lookups. An upval has to go through an extra layer of indirection, whereas an _ENV lookup is a table lookup. Whereas a local is a register in the VM
– Demur Rumed
Jul 28 '17 at 0:30...
When should I use nil and NULL in Objective-C?
...ntions this, but if you dig into objc.h, you'll find the line #define nill __DARWIN_NULL.
– gkb0986
Oct 25 '13 at 3:12
1
...
How can i query for null values in entity framework?
...].[Foos] AS [Extent1]
WHERE (CASE
WHEN (([Extent1].[ProductID] = 1 /* @p__linq__0 */)
AND (NULL /* @p__linq__1 */ IS NOT NULL)) THEN
CASE
WHEN ([Extent1].[ProductStyleID] = NULL /* @p__linq__2 */) THEN cast(1 as bit)
WHEN ([Extent1].[ProductStyleID] <> NULL /* @p__li...
App Inventor 2 Web客户端（Web）详细用法示例 · App Inventor 2 中文网
...件字段名
file
接口约定的表单字段名，PHP 使用 $_FILES['file']
表单字段
列表(列表("title", "照片"))
附加名称/值字段；没有附加字段时用空列表
文件名和 MIME 类型从路径推断，未知类型使用 appli...
App Inventor 2 动态创建组件与布局教程 · App Inventor 2 中文网
... global newButton = DynamicComponents1.CreateComponent("Button", join("btn_", Clock1.Now()))
// 设置新按钮的属性
DynamicComponents1.SetPropertyOfComponent(newButton, "Text", "我是动态按钮")
DynamicComponents1.SetPropertyOfComponent(newButton, "Width", -2) // （表示自动适...
Google Chrome Extensions - Can't load local images with CSS
...
Your image URL should look like chrome-extension://<EXTENSION_ID>/image.jpg
You would be better off replacing css through javascript. From docs:
//Code for displaying <extensionDir>/images/myimage.png:
var imgURL = chrome.extension.getURL("images/myimage.png");
document.getE...