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When would you use delegates in C#? [closed]
...e delegate's invocation.
public class DataProvider
{
protected string _connectionString;
public DataProvider( string psConnectionString )
{
_connectionString = psConnectionString;
}
public void UseReader( string psSELECT, DataReaderUser readerUser )
{
using...
How to post data in PHP using file_get_contents?
I'm using PHP's function file_get_contents() to fetch contents of a URL and then I process headers through the variable $http_response_header .
...
How to force a web browser NOT to cache images
...ile.jpg&some-random-number-262376" />
Script:
// PHP
if( isset( $_GET['img'] ) && is_file( IMG_PATH . $_GET['img'] ) ) {
// read contents
$f = open( IMG_PATH . $_GET['img'] );
$img = $f.read();
$f.close();
// no-cache headers - complete set
// these copied from [php.n...
各编程语言读写文件汇总 - C/C++ - 清泛网 - 专注C/C++及内核技术
各编程语言读写文件汇总all_programming_language_file_read_write_summary读写文件本来是非常基础的代码，但工作学习中难免会有遗忘，有时又难以翻看自己写过的代码，网上搜索更是五花八门让人头大，鉴于此，清泛网 读写文件本来是...
Why are dates calculated from January 1st, 1970?
...
Astronomers use their own epochal date: http://en.wikipedia.org/wiki/Epoch_(astronomy)
Why? A date has to be chosen to make the math work out. Any random date will work.
A date far in the past avoids negative numbers for the general case.
Some of the smarter packages use the proleptic Gregoria...
Is there a max array length limit in C++?
... the size thereof). It is given by the maximum value the system's std::size_t can take. This data type is large enough to contain the size in bytes of any object
The other limit is a physical memory limit. The larger your objects in the array are, the sooner this limit is reached because memory is ...
What's wrong with nullable columns in composite primary keys?
...key creation. If this was just a retrieval problem, you could use where pk_1 = 'a' and pk_2 = 'b' with normal values, and switch to where pk_1 is null and pk_2 = 'b' when there are nulls.
– EoghanM
Mar 15 '13 at 9:59
...
How does free know how much to free?
...
FYI, for example BSD has malloc_size() to reliably access the block size from an malloc()ed pointer. But there's no reliable, portable way.
– laalto
Oct 5 '09 at 7:53
...
How to fix: “UnicodeDecodeError: 'ascii' codec can't decode byte”
... declared in your code using the u prefix to strings. E.g.
>>> my_u = u'my ünicôdé strįng'
>>> type(my_u)
<type 'unicode'>
Unicode strings may also come from file, databases and network modules. When this happens, you don't need to worry about the encoding.
Gotchas
C...
ORA-30926: unable to get a stable set of rows in the source tables
...ates in the query specified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in your query (in fact, if 'Y' is a constant value you don't even need to put it in the query).
Assu...