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Why is document.body null in my javascript?
...g (as mentioned by e-bacho 2.0).
<head>
<title>Javascript Tests</title>
<script type="text/javascript">
window.onload = function() {
var mySpan = document.createElement("span");
mySpan.innerHTML = "This is my span!";
mySpan.style.color...
Why is null an object and what's the difference between null and undefined?
...undefined, null
Booleans: false
Numbers: +0, -0, NaN
Strings: ""
You can test the conversion to boolean by using Boolean as a function (normally it is a constructor, to be used with new):
> Boolean(null)
false
> Boolean("")
false
> Boolean(3-3)
false
> Boolean({})
true
> Boolean([]...
Get/pick an image from Android's built-in Gallery app programmatically
... works with OI file manager, astro file manager AND the media gallery too (tested). so i guess it will work with every file manager (are there many others than those mentioned?). did some corrections to the code he wrote.
public class BrowsePicture extends Activity {
//YOU CAN EDIT THIS TO ...
Pretty-print a Map in Java
...ring, Map<String,double[]>>, then you'll get this type of sting: [test={test=[D@3995ebd8, 2=[D@26fa5067, 3=[D@1d956d37, 4=[D@2cead81, 5=[D@14934d2b}...]
– zygimantus
Jan 16 '16 at 13:23
...
MySQL error: key specification without a key length
... distinct indexed values and total number of rows. Here is one example for test table:
+-----+-----------+
| id | value |
+-----+-----------+
| 1 | abc |
| 2 | abd |
| 3 | adg |
+-----+-----------+
If we index only the first character (N=1), then index table will look...
Check if a string contains a string in C++
... answered Oct 8 '16 at 23:12
Testing123Testing123
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StringBuilder vs String concatenation in toString() in Java
... reference also states that this is optional. In fact, I just did a simple test with JRE 1.6.0_15 and I didn't see any compiler optimization in the decompiled class.
– bruno conde
Oct 7 '09 at 16:07
...
In javascript, is an empty string always false as a boolean?
...
@Bruno, You can perform the same test with NaN and undefined. They are not false but they are falsy. Which is what was asked.
– Joseph
Feb 25 '16 at 23:52
...
How to set session timeout in web.config
...te, you've set the session to be abandoned in 1 minute after its idle.
To test this, create a simple aspx page, and write this code in the Page_Load event,
Response.Write(Session.SessionID);
Open a browser and go to this page. A session id will be printed. Wait for a minute to pass, then hit ref...
How to convert List to List?
...List<string> sss = new List<string>(); IEnumerable<int> test1 = sss.Select<string, int>(x => Convert.ToInt32(x)); but this does not: IEnumerable<int> test2 = sss.Select<string, int>(Convert.ToInt32); The error is ambiguous call between the string,int,int and s...