大约有 40,000 项符合查询结果（耗时：0.0431秒） [XML]
Creating a JSON response using Django and Python
...JSON content.
import json
from django.http import HttpResponse
response_data = {}
response_data['result'] = 'error'
response_data['message'] = 'Some error message'
Pre-Django 1.7 you'd return it like this:
return HttpResponse(json.dumps(response_data), content_type="application/json")
For D...
List of lists changes reflected across sublists unexpectedly
...at you create a new list at each position. One way to do it is
[[1]*4 for _ in range(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's beca...
JavaScript hashmap equivalent
...ache the hash value in the object itself (for example, in a property named __hash).
A hash function which does this is and works for both primitive values and objects is:
function hash(value) {
return (typeof value) + ' ' + (value instanceof Object ?
(value.__hash || (value.__hash = ++ar...
Programmatically retrieve memory usage on iPhone
...icture of usage over-all.
#import <mach/mach.h>
// ...
void report_memory(void) {
struct task_basic_info info;
mach_msg_type_number_t size = TASK_BASIC_INFO_COUNT;
kern_return_t kerr = task_info(mach_task_self(),
TASK_BASIC_INFO,
...
How to concatenate two MP4 files using FFmpeg?
...puts).
ffmpeg -i opening.mkv -i episode.mkv -i ending.mkv \
-filter_complex "[0:v] [0:a] [1:v] [1:a] [2:v] [2:a]
concat=n=3:v=1:a=1 [v] [a]" \
-map "[v]" -map "[a]" output.mkv
Note that this method performs a re-encode.
2. concat demuxer
Use this method wh...
How do I mock a service that returns promise in AngularJS Jasmine unit test?
...ce;
beforeEach(module('app.myService'));
beforeEach(inject( function(_myService_, myOtherService, $q){
myService = _myService_;
spyOn(myOtherService, "makeRemoteCallReturningPromise").and.callFake(function() {
var deferred = $q.defer();
deferred.resolve('Remote call res...
How to determine CPU and memory consumption from inside a process?
... used by current process:
#include "windows.h"
#include "psapi.h"
PROCESS_MEMORY_COUNTERS_EX pmc;
GetProcessMemoryInfo(GetCurrentProcess(), (PROCESS_MEMORY_COUNTERS*)&pmc, sizeof(pmc));
SIZE_T virtualMemUsedByMe = pmc.PrivateUsage;
Total Physical Memory (RAM):
Same code as in "Total Vir...
How to count the number of set bits in a 32-bit integer?
... may need to adjust it to work for a particular language (e.g. using uint32_t for C++ and >>> in Java):
int numberOfSetBits(uint32_t i)
{
// Java: use int, and use >>> instead of >>
// C or C++: use uint32_t
i = i - ((i >> 1) & 0x55555555);
i = (...
How to convert a java.util.List to a Scala list
...
import scala.collection.JavaConversions._
will do implicit conversion for you; e.g.:
var list = new java.util.ArrayList[Int](1,2,3)
list.foreach{println}
share
|
...
How to turn on/off ReactJS 'development mode'?
...tely the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV !== "production")
// do propType checks
The above is the most common pattern, and other libraries follow it as well. So to "disable" t...