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How to check if a file is a valid image file?
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That won't be sufficient if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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Converting JSON String to Dictionary Not List
...datapoints[0][0]). Just to list them, I tried doing datapoints[0:5][0] but all I get is the first datapoint with both elements as opposed to wanting to get the first 5 datapoints containing only the first element. Is there a way to do this?
datapoints[0:5][0] doesn't do what you're expecting. dat...
Better way to sum a property value in an array
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Updated Answer
Due to all the downsides of adding a function to the Array prototype, I am updating this answer to provide an alternative that keeps the syntax similar to the syntax originally requested in the question.
class TravellerCollection e...
LEN function not including trailing spaces in SQL Server
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This is the best, elegant solution so far. I don't really care if it FEELS like a hack or not (coding is not about feelings), I'm really care about the fact that this solution has no side effects. I can change data type varchar/nvarchar and it still works. Good job.
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Can I use jQuery with Node.js?
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Note: The original answer fails to mention that it you will need to install jsdom as well using npm install jsdom
Update (late 2013): The official jQuery team finally took over the management of the jquery package on npm:
npm install jquery
Then:
require("jsdom").env("", function (err, wind...
How do I change the color of the text in a UIPickerView under iOS 7?
...spaced 35 pts apart for a picker height of 180.
Swift 3:
func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
let string = "myString"
return NSAttributedString(string: string, attributes: [NSForegroundColorAtt...
How do I insert NULL values using PDO?
...akes a variable, to reference, and doesn't pull in a value at the time of calling bindParam. I found this in a comment on the php docs:
bindValue(':param', null, PDO::PARAM_INT);
EDIT: P.S. You may be tempted to do this bindValue(':param', null, PDO::PARAM_NULL); but it did not work for everybody...
Eclipse - no Java (JRE) / (JDK) … no virtual machine
... (the first one referenced by your PATH)
Three things to remember:
"Installing" a JRE or a JDK can be as simple as unzipping or copying it from another computer: there is no special installation steps, and you can have as many different JVM versions (1.4, 5.0, 6.0...) as you want, "installed" (co...
How to allow to accept only image files?
...t is very sketchy on mobiles (as of 2015) and by some reports this may actually prevent some mobile browsers from uploading anything at all, so be sure to test your target platforms well.
For detailed browser support, see http://caniuse.com/#feat=input-file-accept
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Serializing PHP object to JSON
...ata->getJsonData());. In essence, implement the function from 5.4, but call it by hand.
Something like this would work, as get_object_vars() is called from inside the class, having access to private/protected variables:
function getJsonData(){
$var = get_object_vars($this);
foreach ($va...