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not None test in Python [duplicate]
...
if val is not None:
# ...
is the Pythonic idiom for testing that a variable is not set to None. This idiom has particular uses in the case of declaring keyword functions with default parameters. is tests identity in Pyt...
关于 __VA_ARGS__ 宽字符版本的问题 - C/C++ - 清泛网 - 专注C/C++及内核技术
关于 __VA_ARGS__ 宽字符版本的问题在写一个可变参数的记录日志函数，考虑到宽字符（Unicode版本）时：#define WIDEN2(x) L ## x#define WIDEN(x) WIDEN2(x)#define __...在写一个可变参数的记录日志函数，考虑到宽字符（Unicode版本）时：
#defin...
LINQ to Entities case sensitive comparison
...ter that it gets filtered again on the client case sensitively. Of course, if you happen to have thousands of entries that match case insensitive, but only one of them is the correct one case sensitive, then it's a lot of overhead. But I don't think that reality will present such scenarios... :)
...
How to get jQuery dropdown value onchange event
I have added two jQuery UI Dropdown Autocomplete script. Now I want get both value onchange of second dropdown and want to store separately in variable. How it is possible?
...
Targeting .NET Framework 4.5 via Visual Studio 2010
...Each version of Visual Studio prior to Visual Studio 2010 is tied to a specific .NET framework. (VS2008 is .NET 3.5, VS2005 is .NET 2.0, VS2003 is .NET1.1) Visual Studio 2010 and beyond allow for targeting of prior framework versions but cannot be used for future releases. You must use Visual Studio...
Flat file databases [closed]
...rt of true: the extension named "SQLite" was discontinued and "SQLite3" is now enabled by default. php.net/manual/en/sqlite.installation.php "Since PHP 5.0 this extension was bundled with PHP. Beginning with PHP 5.4, this extension is available only via PECL." php.net/manual/en/sqlite3.i...
How to convert an array into an object using stdClass() [duplicate]
...Vasile', 'prenume' => 'Mihai', 'sex' => 'm', 'varsta' => 25)
);
If you want to see is this stdClass object just call this
print_r($clasa);
If you want to convert an array to object code will be
$arr = array('a'=>'apple','b'=>'ball');
$arr = (object) $arr;
You don't need to us...
How to export DataTable to Excel
...te(",");
}
}
sw.Write(sw.NewLine);
// Now write all the rows.
foreach (DataRow dr in dt.Rows)
{
for (int i = 0; i < iColCount; i++)
{
if (!Convert.IsDBNull(dr[i]))
{
s...
What's the scope of a variable initialized in an if statement?
... function, class, or module in which they're assigned. Control blocks like if and while blocks don't count, so a variable assigned inside an if is still scoped to a function, class, or module.
(Implicit functions defined by a generator expression or list/set/dict comprehension do count, as do lambd...
When is assembly faster than C?
...(float only has 23 bit and it's harder to predict precision loss). i.e. uniform absolute precision over the entire range, instead of close-to-uniform relative precision (float).
Modern compilers optimize this fixed-point example nicely, so for more modern examples that still need compiler-specif...