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Create a .txt file if doesn't exist, and if it does append a new line
I would like to create a .txt file and write to it, and if the file already exists I just want to append some more lines:
1...
How to check whether dynamically attached event listener exists or not?
...mically attached event listeners exist or not.
The only way you can see if an event listener is attached is by attaching event listeners like this:
elem.onclick = function () { console.log (1) }
You can then test if an event listener was attached to onclick by returning !!elem.onclick (or some...
Switch statement for greater-than/less-than
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1.0 time 37ms 73ms 68ms 184ms 73ms 21ms
if-immediate 1.0 1.0 1.0 2.6 1.0 1.0
if-indirect 1.2 1.8 3.3 3.8 2.6 1.0
switch-immediate 2.0 1.1 2.0 1.0 2.8 1.3
switch-range ...
Android: Difference between onInterceptTouchEvent and dispatchTouchEvent?
What is the difference between onInterceptTouchEvent and dispatchTouchEvent in Android?
14 Answers
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What command means “do nothing” in a conditional in Bash?
... here, I want Bash to do nothing when $a is greater than "10", print "1" if $a is less than "5", otherwise, print "2":
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How do I find out if the GPS of an Android device is enabled
...ger = (LocationManager) getSystemService( Context.LOCATION_SERVICE );
if ( !manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
buildAlertMessageNoGps();
}
private void buildAlertMessageNoGps() {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
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Python list of dictionaries search
...name": "Dick", "age": 12 }
... ]
>>> next(item for item in dicts if item["name"] == "Pam")
{'age': 7, 'name': 'Pam'}
If you need to handle the item not being there, then you can do what user Matt suggested in his comment and provide a default using a slightly different API:
next((item f...
Return None if Dictionary key is not available
I need a way to get a dictionary value if its key exists, or simply return None , if it does not.
11 Answers
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How to know if two arrays have the same values
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function arraysEqual(_arr1, _arr2) {
if (!Array.isArray(_arr1) || ! Array.isArray(_arr2) || _arr1.length !== _arr2.length)
return false;
var arr1 = _arr1.concat().sort();
var arr2 = _arr2.concat().sort();
for (var i = 0; i < arr1.length; i...
Programmatically get the version number of a DLL
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This works if the dll is .net or Win32. Reflection methods only work if the dll is .net. Also, if you use reflection, you have the overhead of loading the whole dll into memory. The below method does not load the assembly into memory.
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