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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));...
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...
Generic method multiple (OR) type constraint
...
Or the compiler could threat the type as an union type within the function and have the return value be of the same type that it gets in. TypeScript does this.
– Alex
Jan 30 '18 at 18:42
...
MySQL error: key specification without a key length
...d, and the trick is to choose a number N that’s long enough to give good selectivity, but short enough to save space. The prefix should be long enough to make the index nearly as useful as it would be if you’d indexed the whole column.
Before we go further let us define some important terms. In...
Get difference between two lists
...the following simple function.
def diff(list1, list2):
c = set(list1).union(set(list2)) # or c = set(list1) | set(list2)
d = set(list1).intersection(set(list2)) # or d = set(list1) & set(list2)
return list(c - d)
or
def diff(list1, list2):
return list(set(list1).symmetric_d...
Find a string by searching all tables in SQL Server Management Studio 2008
...T NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_N...
Calculate a MD5 hash from a string
... (
Encoding.UTF8.GetBytes(observedText)
)
select ba.ToString("x2")
);
}
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How can I validate a string to only allow alphanumeric characters in it?
...n I validate a string using Regular Expressions to only allow alphanumeric characters in it?
10 Answers
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What platforms have something other than 8-bit char?
Every now and then, someone on SO points out that char (aka 'byte') isn't necessarily 8 bits .
12 Answers
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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 ...