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How to check if IEnumerable is null or empty?
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Count() only iterates the enumeration if it can't be cast to an ICollection. In other words, when you call this method, if there's already a Count property on the object, it will just return that and the performance should be identical. Check out the implementation here: refere...
Indentation shortcuts in Visual Studio
I'm new to Visual Studio 2010 and C#. How can I indent the selected text to left/right by using shortcuts?
8 Answers
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In MySQL, how to copy the content of one table to another table within the same database?
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INSERT INTO TARGET_TABLE SELECT * FROM SOURCE_TABLE;
EDIT: or if the tables have different structures you can also:
INSERT INTO TARGET_TABLE (`col1`,`col2`) SELECT `col1`,`col2` FROM SOURCE_TABLE;
EDIT: to constrain this..
INSERT INTO TARGET_TAB...
How do I replace text in a selection?
...e you have open.
There is an icon option which when hovered over says "In Selection" that you can select to find and replace within a selection. I've pointed to the correct icon in the screenshot below.
Hit replace all, and voila, all instances of '0' will be replaced with '255'.
Note: this ...
Service Reference Error: Failed to generate code for the service reference
...types option is there for a reason and in some cases it avoids unnecessary casting in the code consuming the service.
For example, if the service itself is built using WCF and some methods parameters inside it are of type System.Guid, they will be translated to strings in the generated client if th...
Search an Oracle database for tables with specific column names?
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To find all tables with a particular column:
select owner, table_name from all_tab_columns where column_name = 'ID';
To find tables that have any or all of the 4 columns:
select owner, table_name, column_name
from all_tab_columns
where column_name in ('ID', 'FNAME', ...
How to do a JUnit assert on a message in a logger
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@s.d If you cast the Logger to org.apache.logging.log4j.core.Logger (the implementation class for the interface) you'll get access to setAppender()/removeAppender() again.
– David Moles
Dec 10 '19 a...
How to convert SecureString to System.String?
...rtainly use the unsafe keyword and a char*, just call bstr.ToPointer() and cast.
– Ben Voigt
Jun 21 '16 at 16:23
@BenV...
MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
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How to add extra info to copied web text
...cument.location.href}`;
event.clipboardData.setData('text', document.getSelection() + pagelink);
event.preventDefault();
});
Lorem ipsum dolor sit amet, consectetur adipiscing elit.<br/>
<textarea name="textarea" rows="7" cols="50" placeholder="paste your copied text here"></...