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Why does Convert.ToString(null) return a different value if you cast null?
...2f10355736%2fwhy-does-convert-tostringnull-return-a-different-value-if-you-cast-null%23new-answer', 'question_page');
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Query to list number of records in each table in a database
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sp_MSForEachTable 'DECLARE @t AS VARCHAR(MAX);
SELECT @t = CAST(COUNT(1) as VARCHAR(MAX))
+ CHAR(9) + CHAR(9) + ''?'' FROM ? ; PRINT @t'
Output:
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A numeric string as array key in PHP
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Yes, it is possible by array-casting an stdClass object:
$data = new stdClass;
$data->{"12"} = 37;
$data = (array) $data;
var_dump( $data );
That gives you (up to PHP version 7.1):
array(1) {
["12"]=>
int(37)
}
(Update: My original answe...
Can someone explain this 'double negative' trick? [duplicate]
... find it highly intuitive to know what's "falsey" and what's "truthy" when cast to a Boolean.
– Chris
Jul 30 '13 at 3:15
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Can I assume (bool)true == (int)1 for any C++ compiler?
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Yes. The casts are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool....
Strange behavior for Map, parseInt [duplicate]
...sort of. You may use [...].map(parseFloat) or [...].map(Number). Both will cast strings to numbers in the given array. However parseFloat and Number work slightly different than parseInt: both will cast floats as well as integers, while Number will turn strings that start with digits and have other ...
What is the difference between a strongly typed language and a statically typed language?
...ecause any pointer type is convertible to any other pointer type simply by casting. Pascal was intended to be strongly typed, but an oversight in the design (untagged variant records) introduced a loophole into the type system, so technically it is weakly typed.
Examples of truly strongly typed lan...
How can I use PHP to dynamically publish an ical file to be read by Google Calendar?
Any Google search on PHP ical just brings up phpicalendar and how to parse or read IN ical files. I just want to write a PHP file that pulls events from my database and writes them out in ical format.
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[精华] VC中BSTR、Char和CString类型的转换 - C/C++ - 清泛网 - 专注C/C++及内核技术
...t wchar_t *
Right:
BSTR bs = ...; //
...
LPCTSTR sz = static_cast<LPCTSTR>bs;
...
::SysFreeString(bs);
//Never use sz after this line
Wrong:
BSTR bs = ...; //
...
LPCTSTR sz = bs;
...
::SysFreeString(bs);
//Never use sz after this line
_tcslen(sz); //ERROR...
Why don't structs support inheritance?
... The sensible solution to that problem would be to disallow the cast form Base[] to Detived[]. Just like casting from short[] to int[] is forbidden, although casting from short to int is possible.
– Niki
Aug 3 '09 at 16:34
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