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Get all column names of a DataTable into string array using (LINQ/Predicate)
...
Try this (LINQ method syntax):
string[] columnNames = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (fr...
How to convert a Map to List in Java?
...e a wrapper to hold on to the key/value pair).
Say we have a Map:
Map<String, String> m = new HashMap<String, String>();
m.put("Hello", "World");
m.put("Apple", "3.14");
m.put("Another", "Element");
The keys as a List can be obtained by creating a new ArrayList from a Set returned by...
Get pandas.read_csv to read empty values as empty string instead of nan
...das library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can't figure out how to get it not to read an empty value as NaN. Here's sample data and outp...
Binary Data in JSON String. Something better than Base64
...ry data. The binary data has to be escaped so that it can be placed into a string element (i.e. zero or more Unicode chars in double quotes using backslash escapes) in JSON.
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How do you create a Swift Date object?
... initializer which will create a date in the current locale using the date string in the format you specified.
extension NSDate
{
convenience
init(dateString:String) {
let dateStringFormatter = NSDateFormatter()
dateStringFormatter.dateFormat = "yyyy-MM-dd"
dateStringFor...
How to check if an appSettings key exists?
...urationManager.AppSettings[name] != null)
{
// Now do your magic..
}
or
string s = ConfigurationManager.AppSettings["myKey"];
if (!String.IsNullOrEmpty(s))
{
// Key exists
}
else
{
// Key doesn't exist
}
share
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parseInt(null, 24) === 23… wait, what?
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It's converting null to the string "null" and trying to convert it. For radixes 0 through 23, there are no numerals it can convert, so it returns NaN. At 24, "n", the 14th letter, is added to the numeral system. At 31, "u", the 21st letter, is added and...
How to remove time portion of date in C# in DateTime object only?
...bly have the date in following format in object form not in the form of string .
38 Answers
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C++ compiling on Windows and Linux: ifdef switch [duplicate]
... someone looking same in Qt
In Qt
https://wiki.qt.io/Get-OS-name-in-Qt
QString Get::osName()
{
#if defined(Q_OS_ANDROID)
return QLatin1String("android");
#elif defined(Q_OS_BLACKBERRY)
return QLatin1String("blackberry");
#elif defined(Q_OS_IOS)
return QLatin1String("ios");
#elif defin...
Call a stored procedure with parameter in c#
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cmd.Parameters.Add(String parameterName, Object value) is deprecated now. Instead use cmd.Parameters.AddWithValue(String parameterName, Object value)
Add(String parameterName, Object value) has been deprecated. Use AddWithValue(String parame...