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Whether a variable is undefined [duplicate]
...ver return 'undefined' for an empty selection. It always returns an empty string (i.e. ""). .html() will return null if the element doesn't exist though.You need to do:
if(page_name != '')
For other variables that don't come from something like jQuery.val() you would do this though:
if(typeof ...
Curly braces in string in PHP
What is the meaning of { } (curly braces) in string literals in PHP?
5 Answers
5
...
How do I get the file extension of a file in Java?
...le of how to use it (you may specify either full path or just file name):
String ext1 = FilenameUtils.getExtension("/path/to/file/foo.txt"); // returns "txt"
String ext2 = FilenameUtils.getExtension("bar.exe"); // returns "exe"
Maven dependency:
<dependency>
<groupId>commons-io<...
How do I reflect over the members of dynamic object?
... ExpandoObject, the ExpandoObject class actually implements IDictionary<string, object> for its properties, so the solution is as trivial as casting:
IDictionary<string, object> propertyValues = (IDictionary<string, object>)s;
Note that this will not work for general dynamic obj...
Javascript add leading zeroes to date
...
Try this: http://jsfiddle.net/xA5B7/
var MyDate = new Date();
var MyDateString;
MyDate.setDate(MyDate.getDate() + 20);
MyDateString = ('0' + MyDate.getDate()).slice(-2) + '/'
+ ('0' + (MyDate.getMonth()+1)).slice(-2) + '/'
+ MyDate.getFullYear();
EDIT:
To explain,...
How to check if a file exists in the Documents directory in Swift?
...thForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as String
let url = NSURL(fileURLWithPath: path)
if let pathComponent = url.appendingPathComponent("nameOfFileHere") {
let filePath = pathComponent.path
let fileManager = FileManager.default
if fi...
How to convert a string to number in TypeScript?
Given a string representation of a number, how can I convert it to number type in TypeScript?
17 Answers
...
Is it possible to dynamically compile and execute C# code fragments?
...harp;
using System.CodeDom.Compiler;
class Program
{
static void Main(string[] args)
{
var csc = new CSharpCodeProvider(new Dictionary<string, string>() { { "CompilerVersion", "v3.5" } });
var parameters = new CompilerParameters(new[] { "mscorlib.dll", "System.Core.dll...
A Java collection of value pairs? (tuples?)
... where you can define the types of each entry in the map, for example <String, Integer> .
19 Answers
...
Ruby regular expression using variable name
...tr.gsub( /#{var}/, 'foo' ) # => "foo foo foo"
However, if your search string contains metacharacters and you do not want them interpreted as metacharacters, then use Regexp.escape like this:
var = "*This*"
str = "*This* is a string"
p str.gsub( /#{Regexp.escape(var)}/, 'foo' )
# => "foo is ...