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Entity Framework - Code First - Can't Store List
... Great solution for EF Core. Although it seems to have an issue whit char to string conversion. I had to implement it like such: .HasConversion( v => string.Join(";", v), v => v.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries));...
Python Sets vs Lists
...from a sequence, and compute mathematical operations such as intersection, union, difference, and symmetric difference.
Usage
From some of the answers, it is clear that a list is quite faster than a set when iterating over the values. On the other hand, a set is faster than a list when checking if...
How to send a simple string between two programs using pipes?
...lt;sys/types.h>
#include <unistd.h>
int main()
{
int fd;
char * myfifo = "/tmp/myfifo";
/* create the FIFO (named pipe) */
mkfifo(myfifo, 0666);
/* write "Hi" to the FIFO */
fd = open(myfifo, O_WRONLY);
write(fd, "Hi", sizeof("Hi"));
close(fd);
/* rem...
How to get my IP address programmatically on iOS/macOS?
... @"ipv6"
- (NSString *)getIPAddress:(BOOL)preferIPv4
{
NSArray *searchArray = preferIPv4 ?
@[ /*IOS_VPN @"/" IP_ADDR_IPv4, IOS_VPN @"/" IP_ADDR_IPv6,*/ IOS_WIFI @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6, IOS_CELLULAR @"/" IP_ADDR_IPv4, IOS_CELLULAR @"/" IP_ADDR...
In VIM, how do I break one really long line into multiple lines?
... format the line that {motion} moves over
{Visual}gq % format the visually selected area
gqq % format the current line
...
I'd suggest you check out :help gq and :help gw.
Also setting textwidth (tw) will give you auto line break when exceeded during typing. It is used in gq too, though if...
How to append a char to a std::string?
...ing fails with the error prog.cpp:5:13: error: invalid conversion from ‘char’ to ‘const char*’
13 Answers
...
How do I concatenate two strings in C?
... some other languages have. A string in C is just a pointer to an array of char that is terminated by the first null character. There is no string concatenation operator in C.
Use strcat to concatenate two strings. You could use the following function to do it:
#include <stdlib.h>
#include &...
SELECT DISTINCT on one column
...ou're on SQL Server 2005 or greater, you can use a CTE with ROW_NUMBER():
SELECT *
FROM (SELECT ID, SKU, Product,
ROW_NUMBER() OVER (PARTITION BY PRODUCT ORDER BY ID) AS RowNumber
FROM MyTable
WHERE SKU LIKE 'FOO%') AS a
WHERE a.RowNumber = 1
...
Parsing JSON using Json.net
... writing to console):
var tuples = JObject.Parse(myJsonString)["objects"].Select(item => item.ToTuple()).ToList();
tuples.ForEach(t => Console.WriteLine("{0}: ({1},{2})", t.Item1, t.Item2, t.Item3));
share
|...
How do I filter ForeignKey choices in a Django ModelForm?
...tions = super(FrontEndAdmin, self).get_actions(request)
if 'delete_selected' in actions:
del actions['delete_selected']
return actions
prevents delete permission
def has_delete_permission(self, request, obj=None):
return False
filters objects that can be ...