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How can I check a C# variable is an empty string “” or null? [duplicate]
...
Are we to assume that this conversion of stringVar to a cast object returns empty string for both null and empty string assigned to the stringVar variable, but converting the same stringVar without the cast returns null and empty string instead? Im just trying to find out all the ...
What does “dereferencing” a pointer mean?
...le, an int* properly initialised to point to an int variable might - after casting to a float* - access memory in "GPU" memory quite distinct from the memory where the int variable is, then once cast to and used as a function pointer it might point into further distinct memory holding machine opcode...
How to convert a string to an integer in JavaScript?
...ly coercing the string into a number. I prefer to do this explicitly,
var cast = Number("97");
This has different behavior to the parse methods (although it still ignores whitespace). It's more strict: if it doesn't understand the whole of the string than it returns NaN, so you can't use it for s...
Lua string to int
...Integer(number)
return math.floor(tonumber(number) or error("Could not cast '" .. tostring(number) .. "' to number.'"))
end
In which case you explicitly convert the string (or really, whatever it is) into a number, and then truncate the number like an (int) cast would do in Java.
Edit: This ...
SQL query to get all values a enum can have
...ove query will be myenum. Depending on what you are doing, you may need to cast to text. e.g.
SELECT unnest(enum_range(NULL::myenum))::text
If you want to specify the column name, you can append AS my_col_name.
Credit to Justin Ohms for pointing out some additional tips, which I incorporated...
Most efficient way to check for DBNull and then assign to a variable?
...ert(Of Integer)(oRow("Value")), iDefault)
oSomeObject.StringMember = If(TryCast(oRow("Name"), String), sDefault)
Function TryConvert(Of T As Structure)(ByVal obj As Object) As T?
If TypeOf obj Is T Then
Return New T?(DirectCast(obj, T))
Else
Return Nothing
End If
End Fun...
SQL select only rows with max value on a column [duplicate]
...'s how it looks with the above example, written in SQL
SELECT id,
CAST(SUBSTRING(max(packed_col) FROM 2 FOR 6) AS float) as max_rev,
SUBSTRING(max(packed_col) FROM 11) AS content_for_max_rev
FROM (SELECT id,
CAST(1000 + rev + .001 as CHAR) || '---' || CAST(content AS char) ...
Use a LIKE statement on SQL Server XML Datatype
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Yet another option is to cast the XML as nvarchar, and then search for the given string as if the XML vas a nvarchar field.
SELECT *
FROM Table
WHERE CAST(Column as nvarchar(max)) LIKE '%TEST%'
I love this solution as it is clean, easy to remembe...
Filling a DataSet or DataTable from a LINQ query result set
...ons.Generic.IEnumerable'. An explicit conversion exists (are you missing a cast?)
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What are major differences between C# and Java?
...es over Java, many of which, such as operator overloading and user-defined casts, are already familiar to the large community of C++ programmers.
• Event handling is a "first class citizen"—it is part of the language itself.
• Allows the definition of "structs", which are similar to clas...