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What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
What does the double colon (::) mean in CSS?
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It means pseudo element selector. It means the element to the right doesn't exist in the normal DOM, but can be selected.
A pseudo-element is made of two colons (::) followed by the name of the pseudo-element.
Source
It was originally only a ...
iOS - Dismiss keyboard when touching outside of UITextField
... the view, and then call resign first responder on the UITextField on it's selector.
The code:
In viewDidLoad
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(dismissKeyboard)];
[self.view addGestureRecognizer:tap];
In dismissKeyboard:
-(void)...
How to allow to accept only image files?
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That should be the selected answer! It just lack a note saying that you still need to check server-side (because of non supporting browser, but also for security)
– Erdal G.
Dec 19 '15 at 13:40
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How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
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In "Elements" panel, press Ctrl+F
In the search box, type in XPath or CSS Selector, if elements are found, they will be highlighted in yellow.
Firefox (since version 75)
Since FF 75 it's possible to use raw xpath query without evaluation xpath expressions, see documentation for more info.
Fir...
Repair all tables in one go
...ing query to print REPAIR SQL statments for all tables inside a database:
select concat('REPAIR TABLE ', table_name, ';') from information_schema.tables
where table_schema='mydatabase';
After that copy all the queries and execute it on mydatabase.
Note: replace mydatabase with desired DB name
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The type or namespace name 'Objects' does not exist in the namespace 'System.Data'
...ontext.tt and be nested under your edmx file in Solution Explorer. You can select the templates in Solution Explorer and press the Del key to delete them.
Note: In Web Site projects the templates will not be nested under your edmx file, but listed alongside it in Solution Explorer.
Note: In VB.N...
How to re-create database for Entity Framework?
...database from SQL Server Object Explorer in Visual Studio.
Right-click and select delete.
Delete mdf and ldf files from file system - if they are still there.
Rebuild Solution.
Start Application - database will be re-created.
...
How to select where ID in Array Rails ActiveRecord without exception
When I have array of ids, like
6 Answers
6
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Which MySQL datatype to use for an IP address? [duplicate]
...nvert them:
INSERT INTO `table` (`ipv4`) VALUES (INET_ATON("127.0.0.1"));
SELECT INET_NTOA(`ipv4`) FROM `table`;
For IPv6 addresses you could use a BINARY instead:
`ipv6` BINARY(16)
And use PHP’s inet_pton and inet_ntop for conversion:
'INSERT INTO `table` (`ipv6`) VALUES ("'.mysqli_real_es...