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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) {...
How do I remove the “extended attributes” on a file in Mac OS X?
...
Answer (Individual Files)
1. Showcase keys to use in selection.
xattr ~/Desktop/screenshot\ 2019-10-23\ at\ 010212.png
# com.apple.FinderInfo
# com.apple.lastuseddate#PS
# com.apple.metadata:kMDItemIsScreenCapture
# com.apple.metadata:kMDItemScreenCaptureGlobal...
ASP.NET MVC: Custom Validation by DataAnnotation
...ntext validationContext)
{
var properties = this.PropertyNames.Select(validationContext.ObjectType.GetProperty);
var values = properties.Select(p => p.GetValue(validationContext.ObjectInstance, null)).OfType<string>();
var totalLength = values.Sum(x => x.Lengt...
How to quickly edit values in table in SQL Server Management Studio?
...
Go to Tools > Options. In the tree on the left, select SQL Server Object Explorer. Set the option "Value for Edit Top Rows command" to 0. It'll now allow you to view and edit the entire table from the context menu.
...
Access restriction on class due to restriction on required library rt.jar?
...ings in the project properties.
Remove the JRE System Library
Add it back; Select "Add Library" and select the JRE System Library. The default worked for me.
This works because you have multiple classes in different jar files. Removing and re-adding the JRE lib will make the right classes be first...
Can I have multiple primary keys in a single table?
...hese practices, but there is nothing in the relational model that requires selecting a primary key among the candidate keys.
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What is PAGEIOLATCH_SH wait type in SQL Server?
...ppens in queries that use indexes efficiently.
If your query is like this:
Select * from <table> where <col1> = <value> order by <PrimaryKey>
, check that you have a composite index on (col1, col_primary_key).
If you don't have one, then you'll need either a full INDEX SCAN ...
ArrayList initialization equivalent to array initialization [duplicate]
...
The selected answer is: ArrayList<Integer>(Arrays.asList(1,2,3,5,8,13,21));
However, its important to understand the selected answer internally copies the elements several times before creating the final array, and that th...
Are email addresses case sensitive?
...eudocode:
if (user.paidEmailFee) {
// case sensitive email
query = "select * from users where email LIKE ' + user.email + '"
} else {
// case insensitive email
query = "select * from users where email ILIKE ' + user.email + '"
}
This way, you are mostly enforcing case insensitivity bu...
JPQL IN clause: Java-Arrays (or Lists, Sets…)?
... for JPA 1.0 but you can pass a Collection in JPA 2.0:
String qlString = "select item from Item item where item.name IN :names";
Query q = em.createQuery(qlString, Item.class);
List<String> names = Arrays.asList("foo", "bar");
q.setParameter("names", names);
List<Item> actual = q.get...