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How can I clear an HTML file input with JavaScript?
...d the file input element to this new form and reset it. This way works for all browsers.
I wrote a javascript function. demo: http://jsbin.com/muhipoye/1/
function clearInputFile(f){
if(f.value){
try{
f.value = ''; //for IE11, latest Chrome/Firefox/Opera...
}catch(...
Simple explanation of MapReduce?
...
Going all the way down to the basics for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2...
How do I check that multiple keys are in a dict in a single pass?
...
Well, you could do this:
>>> if all (k in foo for k in ("foo","bar")):
... print "They're there!"
...
They're there!
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SQL query return data from multiple tables
...I-89 syntax (and if you are used to 89, may seem much less intuitive - but all I can say is to try it) as it is much easier to understand when the queries start getting more complex. Why use it? Is there a performance gain? The short answer is no, but it is easier to read once you get used to it. It...
What is a 'Closure'?
... scope
When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languag...
Git add and commit in one command
...
is an easy way to tell git to delete files you have deleted, but I generally don't recommend such catch-all workflows. Git commits should in best practice be fairly atomic and only affect a few files.
git add .
git commit -m "message"
is an easy way to add all files new or modified. Also, the ...
How do you find the sum of all the numbers in an array in Java?
I'm having a problem finding the sum of all of the integers in an array in Java. I cannot find any useful method in the Math class for this.
...
Acronyms in CamelCase [closed]
...n you use an abbreviation or acronym that is two characters long, put them all in caps;
When the acronym is longer than two chars, use a capital for the first character.
So, in your specific case, getUnescoProperties() is correct.
...
Can I catch multiple Java exceptions in the same catch clause?
...tch (IOException | SQLException ex) {
...
}
Remember, though, that if all the exceptions belong to the same class hierarchy, you can simply catch that base exception type.
Also note that you cannot catch both ExceptionA and ExceptionB in the same block if ExceptionB is inherited, either direct...
What are the performance characteristics of sqlite with very large database files? [closed]
...a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices.
The idea was to insert enough data until sqlite files were about 50GB.
Single Table
I tried to insert multiple rows into a sqlite file with just one table. When the file was about 7GB (sorry I ...