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In where shall I use isset() and !empty()
.....) contains some non-empty data.
To answer question 1 :
$str = '';
var_dump(isset($str));
gives
boolean true
Because the variable $str exists.
And question 2 :
You should use isset to determine whether a variable exists ; for instance, if you are getting some data as an array, you migh...
Get IP address of visitors using Flask for Python
...est object and then get from this same Request object, the attribute remote_addr.
Code example
from flask import request
from flask import jsonify
@app.route("/get_my_ip", methods=["GET"])
def get_my_ip():
return jsonify({'ip': request.remote_addr}), 200
For more information see the Werkzeu...
How to get the error message from the error code returned by GetLastError()?
...rror message has been recorded
LPSTR messageBuffer = nullptr;
size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, errorMessageID, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&a...
Mongoose query where value is not null
...ry The up-to-date doc about it, is here: mongoosejs.com/docs/api.html#query_Query-ne
– zeropaper
Jul 20 '14 at 7:52
Ho...
Can a variable number of arguments be passed to a function?
... this. The key point is that the general signature of a function is f(*list_args, **keyword_args) (not f(*list_args)).
– Eric O Lebigot
Mar 15 '13 at 3:36
...
How can I select and upload multiple files with HTML and PHP, using HTTP POST?
...nctype="multipart/form-data">
<input type="file" name="my_file[]" multiple>
<input type="submit" value="Upload">
</form>
<?php
if (isset($_FILES['my_file'])) {
$myFile = $_FILES['my_file'];
$f...
Execution time of C program
...es calculating the number of clocks the program took divided by the Clocks_per_second value.
16 Answers
...
What's Mongoose error Cast to ObjectId failed for value XXX at path “_id”?
...ng a request to /customers/41224d776a326fb40f000001 and a document with _id 41224d776a326fb40f000001 does not exist, doc is null and I'm returning a 404 :
...
How to efficiently compare two unordered lists (not sets) in Python?
... objects are not unhashable per se. You just have to implements a sensible __hash__, but that might be impossible for collections.
– Jochen Ritzel
Oct 19 '11 at 22:23
...
How to avoid annoying error “declared and not used”
..., if you really want to skip this error, you can use the blank identifier (_) :
package main
import (
"fmt" // imported and not used: "fmt"
)
func main() {
i := 1 // i declared and not used
}
becomes
package main
import (
_ "fmt" // no more error
)
func main() {
i := 1 // no ...