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What are the differences between delegates and events?
...custom user control that shows the properties of that person. When someone selects a person in the drop-down the labels in the user control update to show the properties of the person selected.
Here is how that works. We have three files that help us put this together:
Mediator.cs -- static cla...
LINQ Aggregate algorithm explained
...ggregate help readability? In general I love LINQ because I think .Where, .Select, .OrderBy and so on greatly helps readability (if you avoid inlined hierarhical .Selects). Aggregate has to be in Linq for completeness reasons but personally I am not so convinced that .Aggregate adds readability comp...
Picking a random element from a set
... the buckets that make up the hashset, which allows us to more efficiently select a random elements. If random elements are necessary in Java, it might be worthwhile to define a custom hash set that allows the user to look under the hood. See [boost's docs][1] for a little more in this. [1] boos...
Datatable vs Dataset
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One feature of the DataSet is that if you can call multiple select statements in your stored procedures, the DataSet will have one DataTable for each.
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Enable the display of line numbers in Visual Studio
...disappeared at some point, even though the tools/options check showed them selected. As @TH Todorov stated, I had to go back, uncheck, then recheck them and save for them to reappear.
– BentChainRing
Oct 4 '17 at 18:49
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How should you build your database from source control?
... I'm assuming "look up lists" means the data that is used to populuate <select> boxes? That may not always be possible, since that data might be modified by users (in some way) on production. Keeping backups makes sense in this case. You also suggest recreating the database from scratch as ...
How to define a custom ORDER BY order in mySQL
...in the order you specify.
The second will involve a case somewhere, i.e.
SELECT * FROM table
ORDER BY CASE Language
WHEN 'ENU' THEN 3
WHEN 'JPN' THEN 2
WHEN 'DAN' THEN 1
ELSE 0
END DESC, ID ASC
Performance-wise the ENUM method will return faster results, but be more hassle if you...
How to convert an IPv4 address into a integer in C#?
...actually checks the endianness, here goes:
byte[] ip = address.Split('.').Select(s => Byte.Parse(s)).ToArray();
if (BitConverter.IsLittleEndian) {
Array.Reverse(ip);
}
int num = BitConverter.ToInt32(ip, 0);
and back:
byte[] ip = BitConverter.GetBytes(num);
if (BitConverter.IsLittleEndian) {...
OrderBy descending in Lambda expression?
... orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person => person.Name)
.ThenByDescending(person => person.Age)
.Select(person => person.Name);
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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
...table.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't need the VALUES syntax if you are using a SELECT to populate the INSERT values.
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