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@try - catch block in Objective-C
...
All work perfectly :)
NSString *test = @"test";
unichar a;
int index = 5;
@try {
a = [test characterAtIndex:index];
}
@catch (NSException *exception) {
NSLog(@"%@", exception.reason);
NSLog(@"Char at in...
How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
Can't open config file: /usr/local/ssl/openssl.cnf on Windows [duplicate]
...
The solution is running this command:
set OPENSSL_CONF=C:\OpenSSL-Win32\bin\openssl.cfg
or
set OPENSSL_CONF=[path-to-OpenSSL-install-dir]\bin\openssl.cfg
in the command prompt before using openssl command.
Let openssl know for sure where to find its .cfg file.
Al...
C# code to validate email address
...e-mail addresses are more forgiving than you might first assume. These are all perfectly valid forms:
cog@wheel
"cogwheel the orange"@example.com
123@$.xyz
For most use cases, a false "invalid" is much worse for your users and future proofing than a false "valid". Here's an article that used to ...
Populate a Razor Section From a Partial
...n the Scripts section of your view:
@section Scripts
{
@Html.Partial("_Scripts", "ScriptName_For_Partial1")
}
Again, it might not win a beauty prize but it will work.
share
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improve this ans...
Which way is best for creating an object in JavaScript? Is `var` necessary before an object property
...your example, Person (you should start the name with a capital letter) is called the constructor function. This is similar to classes in other OO languages.
Use way 2 if you only need one object of a kind (like a singleton). If you want this object to inherit from another one, then you have to use a...
How do you run a SQL Server query from PowerShell?
... would use the following. It is what we use at my company.
$ServerName = "_ServerName_"
$DatabaseName = "_DatabaseName_"
$Query = "SELECT * FROM Table WHERE Column = ''"
#Timeout parameters
$QueryTimeout = 120
$ConnectionTimeout = 30
#Action of connecting to the Database and executing the query a...
How do I download a tarball from GitHub using cURL?
I am trying to download a tarball from GitHub using cURL , but it does not seem to be redirecting:
5 Answers
...
What's the meaning of interface{}?
...interface that has no methods.
Since there is no implements keyword, all types implement at least zero methods, and satisfying an interface is done automatically, all types satisfy the empty interface.
That means that if you write a function that takes an interface{} value as a parameter, yo...
Maximum number of records in a MySQL database table
... The poster is not asking about numeric or any other data types. . I really do not understand how this can be flagged as a correct answer. Though I must admit that the question is ambiguous we should distinguish between PK data type and maximum number of rows for a table.
–...