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Can anyone explain IEnumerable and IEnumerator to me? [closed]
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for example, when to use it over foreach?
You don't use IEnumerable "over" foreach. Implementing IEnumerable makes using foreach possible.
When you write code like:
foreach (Foo bar in baz)
{
...
}
it's functionally equivalent to writing:
...
How to execute a Ruby script in Terminal?
I've set everything up that I need on my Mac (Ruby, Rails, Homebrew, Git, etc), and I've even written a small program. Now, how do I execute it in Terminal? I wrote the program in Redcar and saved it as a .rb, but I don't know how to execute it through Terminal. I want to run the program and see if ...
Nullable type as a generic parameter possible?
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Change the return type to Nullable<T>, and call the method with the non nullable parameter
static void Main(string[] args)
{
int? i = GetValueOrNull<int>(null, string.Empty);
}
public static Nullable<T> GetValueOrNull<T>(DbDataRecord reader, string columnName) ...
How much size “Null” value takes in SQL Server
I have a large table with say 10 columns. 4 of them remains null most of the times. I have a query that does null value takes any size or no size in bytes. I read few articles some of them are saying :
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The Role Manager feature has not been enabled
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You can do this by reading from the boolean property at:
System.Web.Security.Roles.Enabled
This is a direct read from the enabled attribute of the roleManager element in the web.config:
<configuration>
<system.web>
<roleManager enabled="true" />
</system.web>
<...
How to handle click event in Button Column in Datagridview?
...'ve added a button to your DataGridView and you want to run some code when it's clicked.
Easy peasy - just follow these steps:
Don'ts:
First, here's what NOT to do:
I would avoid the suggestions in some of the other answers here and even provided by the documentation at MSDN to hardcode the column i...
Why use apparently meaningless do-while and if-else statements in macros?
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The do ... while and if ... else are there to make it so that a
semicolon after your macro always means the same thing. Let's say you
had something like your second macro.
#define BAR(X) f(x); g(x)
Now if you were to use BAR(X); in an if ... else statement, where the bodi...
Lock Escalation - What's happening here?
...ked the Generate Change Script button and I noticed that the change script it generated drops the column, says "go" and then runs an additional ALTER TABLE statement that appears to set the lock escalation for the table to "TABLE". Example:
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How to import an excel file in to a MySQL database
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Export it into some text format. The easiest will probably be a tab-delimited version, but CSV can work as well.
Use the load data capability. See http://dev.mysql.com/doc/refman/5.1/en/load-data.html
Look half way down the page, as...
How do I auto-reload a Chrome extension I'm developing?
...ome extension to reload every time I save a file in the extension folder, without having to explicitly click "reload" in chrome://extensions/. Is this possible?
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