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Forced naming of parameters in Python
...ed.
Cons:
Checking occurs during run-time, not compile-time.
Use of an extra parameter (though not argument) and an additional check. Small performance degradation respect to regular functions.
Functionality is a hack without direct support by the language (see note below).
When calling the fun...
Can you get the column names from a SqlDataReader?
...
var reader = cmd.ExecuteReader();
var columns = new List<string>();
for(int i=0;i<reader.FieldCount;i++)
{
columns.Add(reader.GetName(i));
}
or
var columns = Enumerable.Range(0, reader.FieldCount).Select(reader.GetName).ToList();
...
Why malloc+memset is slower than calloc?
...en though it is already filled with zeroes. This is an enormous amount of extra work, and explains why calloc() is faster than malloc() and memset(). If end up using the memory anyway, calloc() is still faster than malloc() and memset() but the difference is not quite so ridiculous.
This doesn'...
Example JavaScript code to parse CSV data
...http://stackoverflow.com/a/1293163/2343
// This will parse a delimited string into an array of
// arrays. The default delimiter is the comma, but this
// can be overriden in the second argument.
function CSVToArray( strData, strDelimiter ){
// Check to see if the delimiter is...
Adding a new array element to a JSON object
... parse it so you can apply the changes to a native JavaScript Object, then stringify back to JSON
var jsonStr = '{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';
var obj = JSON.parse(jsonStr);
obj['theTeam'].push({"teamId":"4","sta...
Convert Newtonsoft.Json.Linq.JArray to a list of specific object type
...= ((JArray)array).Select(x => new SelectableEnumItem
{
FirstName = (string)x["first_name"],
Selected = (bool)x["selected"]
}).ToList();
share
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Capture HTML Canvas as gif/jpg/png/pdf?
...(img);. The document.write code is making the data URL, them making a HTML string, then putting a copy of that string in the DOM, the browser then has to parse that HTML string, put another copy on the image element, then parse it again to turn the data URL into image data, then finally it can show ...
Validate a username and password against Active Directory?
...
namespace ProtocolTest
{
class Program
{
static void Main(string[] args)
{
try
{
LdapConnection connection = new LdapConnection("ldap.fabrikam.com");
NetworkCredential credential = new NetworkCredential("user", "passwor...
Catch a thread's exception in the caller thread in Python
...rns to the main thread immediately when an exception is called
requires no extra user defined classes because it does not need:
an explicit Queue
to add an except else around your work thread
Source:
#!/usr/bin/env python3
import concurrent.futures
import time
def func_that_raises(do_raise)...
How to update column with null value
...have tried this many different ways and the best I have gotten is an empty string.
13 Answers
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