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URL encoding the space character: + or %20?
...form that uses +. So you're most likely to only see + in URLs in the query string after an ?.
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The cast to value type 'Int32' failed because the materialized value is null
...ky abstraction" that yields unexpected behaviour.
One such case is null handling, where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more gene...
Converting from IEnumerable to List [duplicate]
...rrayList();
_provinces.Add("Western");
_provinces.Add("Eastern");
List<string> provinces = _provinces.Cast<string>().ToList();
If you're using Generic version IEnumerable<T>, The conversion is straight forward. Since both are generics, you can do like below,
IEnumerable<in...
jQuery $(“#radioButton”).change(…) not firing during de-selection
... answered Mar 3 '11 at 5:08
AndomarAndomar
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Determining the current foreground application from a background task or service
...ts it, then you can easily access details of the foreground app/activity:
String foregroundTaskPackageName = foregroundTaskInfo .topActivity.getPackageName();
PackageManager pm = AppService.this.getPackageManager();
PackageInfo foregroundAppPackageInfo = pm.getPackageInfo(foregroundTaskPackageName,...
Convert pem key to ssh-rsa format
...PubKey = NULL;
RSA* pRsa = NULL;
BIO *bio, *b64;
ERR_load_crypto_strings();
OpenSSL_add_all_algorithms();
if (argc != 3)
{
printf("usage: %s public_key_file_name ssh_key_description\n", argv[0]);
iRet = 1;
goto error;
}
pFile = fopen(argv[1], "rt");
i...
Detect Safari using jQuery
...
Using a mix of feature detection and Useragent string:
var is_opera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
var is_Edge = navigator.userAgent.indexOf("Edge") > -1;
var is_chrome = !!window.chrome && !is_opera && !i...
What happens to an open file handle on Linux if the pointed file gets moved or deleted
...ntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <strings.h>
#include <stdio.h>
void perror_and_exit() {
perror(NULL);
exit(1);
}
int main(int argc, char *argv[]) {
int fd;
if ((fd = open("data", O_RDONLY)) == -1) {
perror_and_exit();
}
char buf[5]...
Selecting multiple columns in a pandas dataframe
...
The column names (which are strings) cannot be sliced in the manner you tried.
Here you have a couple of options. If you know from context which variables you want to slice out, you can just return a view of only those columns by passing a list into the...
How to check if a database exists in SQL Server?
...n general it's because Microsoft commits to the format INFORMATION_SCHEMA, and reserves the right to change the system tables as they please. But in this case, after looking more closely, INFORMATION_SCHEMA doesn't work, so this is probably the best option.
– mwigdahl
...