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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...
SQL NVARCHAR and VARCHAR Limits
... large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the statement
...
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...
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...
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...
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
...
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
...
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
...
Calculate a MD5 hash from a string
... (
Encoding.UTF8.GetBytes(observedText)
)
select ba.ToString("x2")
);
}
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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 ...