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Check if PHP session has already started
I have a PHP file that is sometimes called from a page that has started a session and sometimes from a page that doesn't have session started. Therefore when I have session_start() on this script I sometimes get the error message for "session already started". For that I've put these lines:
...
Get nth character of a string in Swift programming language
...ng a linear loop inside another linear loop means this for loop is accidentally O(n2) — as the length of the string increases, the time this loop takes increases quadratically. Instead of doing that you could use the characters's string collection.
– ignaciohugog
...
Why do Java programmers like to name a variable “clazz”? [closed]
...nvention ? I think 'clazz' is not even an English word , has no meaning at all , how can so many programmers name a wrong name coincidentally ?
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ios Upload Image and Text using HTTP POST
...programmed to accept.
NSMutableDictionary* _params = [[NSMutableDictionary alloc] init];
[_params setObject:[NSString stringWithString:@"1.0"] forKey:[NSString stringWithString:@"ver"]];
[_params setObject:[NSString stringWithString:@"en"] forKey:[NSString stringWithString:@"lan"]];
[_params setObje...
Can iterators be reset in Python?
...ary data needs to be
stored). In general, if one iterator
uses most or all of the data before
another iterator starts, it is faster
to use list() instead of tee().
Basically, tee is designed for those situation where two (or more) clones of one iterator, while "getting out of sync" with ea...
GridCtrl 控件FAQ - C/C++ - 清泛网 - 专注C/C++及内核技术
... BOOL DeleteRow(int nRow);
BOOL DeleteNonFixedRows();
BOOL DeleteAllItems();
11.可以在第一个单元格中加入Check控件
A：
#include "NewCellTypes/GridCellCheck.h"//包含头文件
BOOL CGridCtrl::SetCellType(int nRow, int nCol, CRuntimeClass* pRuntime...
Redirecting Output from within Batch file
... good and fast way that only opens and positions the file once
@echo off
call :sub >output.txt
exit /b
:sub
command1
command2
...
commandN
Edit 2020-04-17
Every now and then you may want to repeatedly write to two or more files. You might also want different messages on the screen. It is sti...
How to identify server IP address in PHP
... This is NOT the server address! This is the address the remote browser calls the server, which is under control of the remote user. Use the answer by John K instead
– Ariel
Feb 12 '15 at 10:36
...
Execute code when Django starts ONCE only?
... entirely a separate problem. The idea of special one-time startup before all management commands is hard to understand. You'll have to provide something specific. Perhaps in another question.
– S.Lott
Feb 13 '12 at 12:49
...
What is lexical scope?
...
I understand them through examples. :)
First, lexical scope (also called static scope), in C-like syntax:
void fun()
{
int x = 5;
void fun2()
{
printf("%d", x);
}
}
Every inner level can access its outer levels.
There is another way, called dynamic scope used by ...