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C++ Convert string (or char*) to wstring (or wchar_t*)
...nclude <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = converter.to_bytes(wide_utf16_source_string);
std::wstring wide = converter.from_bytes(narrow_utf8_source_string);
Longer online compilable and runnable example:
(They all sho...
How to create CSV Excel file C#? [closed]
...Object = obj;
var line = String.Join(delimeter, propertyInfos.Select(x => SanitizeValuesForCSV(x.GetValue(localObject, null), delimeter)));
sb.AppendLine(line);
}
return sb.ToString();
}
private static string SanitizeValuesForCSV(object value, s...
Determine the number of lines within a text file
...lt is another problem as you read the whole file just to count the newline character(s),
At some point, someone is going to have to read the characters in the file, regardless if this the framework or if it is your code. This means you have to open the file and read it into memory if the file is la...
Convert seconds to Hour:Minute:Second
...ed to that of the TIME data type, which is from -838:59:59 to 838:59:59 :
SELECT SEC_TO_TIME(8525);
# 02:22:05
See: SEC_TO_TIME
Run the Demo
PostgreSQL example:
SELECT TO_CHAR('8525 second'::interval, 'HH24:MI:SS');
# 02:22:05
Run the Demo
...
RegEx to make sure that the string contains at least one lower case char, upper case char, digit and
What is the regex to make sure that a given string contains at least one character from each of the following categories.
...
List columns with indexes in PostgreSQL
...constraint uk_test3ab unique (a, b));
List indexes and columns indexed:
select
t.relname as table_name,
i.relname as index_name,
a.attname as column_name
from
pg_class t,
pg_class i,
pg_index ix,
pg_attribute a
where
t.oid = ix.indrelid
and i.oid = ix.indexreli...
Unresolved external symbol on static class members
...ou must add the definitions to match your declarations of X and Y
unsigned char test::X;
unsigned char test::Y;
somewhere. You might want to also initialize a static member
unsigned char test::X = 4;
and again, you do that in the definition (usually in a CXX file) not in the declaration (which is...
Uint8Array to string in Javascript
... string (I believe Javascript uses 16 bit Unicode)? I dont want to add one character at the time as the string concaternation would become to CPU intensive.
...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...