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How to get error message when ifstream open fails
How to get error message as string?
4 Answers
4
...
Create Django model or update if exists
...a value that evaluates
to True (i.e., a value other than None or the empty string), Django
executes an UPDATE. If the object’s primary key attribute is not set
or if the UPDATE didn’t update anything, Django executes an INSERT.
It's worth noting that when they say 'if the UPDATE didn't update a...
How to use ELMAH to manually log errors
...mah
/// </summary>
public static void LogError(Exception ex, string contextualMessage=null)
{
try
{
// log error to Elmah
if (contextualMessage != null)
{
// log exception with contextual information that's visibl...
Detecting iOS / Android Operating system
...
You can test the user agent string:
/**
* Determine the mobile operating system.
* This function returns one of 'iOS', 'Android', 'Windows Phone', or 'unknown'.
*
* @returns {String}
*/
function getMobileOperatingSystem() {
var userAgent = navig...
MongoDB: How to update multiple documents with a single command?
...
How to do it for oldvalue+"some string"
– Mahesh K
Nov 14 '17 at 11:03
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Can angularjs routes have optional parameter values?
...enerating-the-templateurl
You can use a function to generate the template string:
var app = angular.module('app',[]);
app.config(
function($routeProvider) {
$routeProvider.
when('/', {templateUrl:'/home'}).
when('/users/:user_id',
{
...
Parse a .py file, read the AST, modify it, then write back the modified source code
...de="exec"))
Hello Python!!
You can parse the python code (represented in string) by simply calling the API ast.parse(). This returns the handle to Abstract Syntax Tree (AST) structure. Interestingly you can compile back this structure and execute it as shown above.
Another very useful API is ast....
How to create multiple directories from a single full path in C#?
...
Create directories from complete filepath
private String EvaluatePath(String path){
try
{
String folder = Path.GetDirectoryName(path);
if (!Directory.Exists(folder))
{
// Try to create the directory.
DirectoryInfo di =...
Grepping a huge file (80GB) any way to speed it up?
...ocale instead of UTF-8.
2) Use fgrep because you're searching for a fixed string, not a regular expression.
3) Remove the -i option, if you don't need it.
So your command becomes:
LC_ALL=C fgrep -A 5 -B 5 'db_pd.Clients' eightygigsfile.sql
It will also be faster if you copy your file to RAM di...
Convert Linq Query Result to Dictionary
...n keyCollections = dict.Keys;
ICOllection valueCollections = dict.Values;
String[] myKeys = new String[dict.Count];
String[] myValues = new String[dict.Count];
keyCollections.CopyTo(myKeys,0);
valueCollections.CopyTo(myValues,0);
for(int i=0; i<dict.Count; i++)
{
Console.WriteLine("Key: " + my...