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How do I get the directory from a file's full path?
...are working with a FileInfo object, then there is an easy way to extract a string representation of the directory's full path via the DirectoryName property.
Description of the FileInfo.DirectoryName Property via MSDN:
Gets a string representing the directory's full path.
Sample usage:
stri...
Parse v. TryParse
...
If the string can not be converted to an integer, then
int.Parse() will throw an exception
int.TryParse() will return false (but not throw an exception)
...
Is there “0b” or something similar to represent a binary number in Javascript
...nd octal (prefix 0) formats.
One possible alternative is to pass a binary string to the parseInt method along with the radix:
var foo = parseInt('1111', 2); // foo will be set to 15
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|
im...
Python extract pattern matches
...need to capture from regex. search for the pattern, if found, retrieve the string using group(index). Assuming valid checks are performed:
>>> p = re.compile("name (.*) is valid")
>>> result = p.search(s)
>>> result
<_sre.SRE_Match object at 0x10555e738>
>>>...
Search and replace a line in a file in Python
...
Note that files should be a string containing the file name, not a file object.
– atomh33ls
Aug 30 '13 at 10:00
...
machine learning libraries in C# [closed]
...2 helper classes:
public class TrainingSet
{
private readonly List<string> _attributes = new List<string>();
private readonly List<List<object>> _examples = new List<List<object>>();
public TrainingSet(params string[] attributes)
{
_attribu...
Set value to NULL in MySQL
...d'] == '')) {
$val = 'NULL';
} else {
$val = "'" . mysql_real_escape_string($_POST['nullfield']) . "'";
}
$sql = "INSERT INTO .... VALUES ($val)";
if you put 'NULL' into your query, then you're just inserting a 4-character string. Without the quotes, NULL is the actual null value.
...
E11000 duplicate key error index in mongodb mongoose
...
var userSchema = new mongoose.Schema({
local: {
name: { type: String },
email : { type: String, require: true, index:true, unique:true,sparse:true},
password: { type: String, require:true },
},
facebook: {
id : { type: String },
token : { type:...
Shorter syntax for casting from a List to a List?
...ist<object>();
o.Add("one");
o.Add("two");
o.Add(3);
IEnumerable<string> s1 = o.Cast<string>(); //fails on the 3rd item
List<string> s2 = o.ConvertAll(x => x.ToString()); //succeeds
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...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...y objects returned.
Consider:
class House
{
int Id { get; set; }
string Address { get; set; }
Person[] Inhabitants { get; set; }
}
class Person
{
string Name { get; set; }
int HouseId { get; set; }
}
and tables with a similar structure. A single query for the address "22 Va...