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How to do ToString for a possibly null object?
...# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "").ToString()
to be even more concise.
Unfo...
MongoDB SELECT COUNT GROUP BY
...
I need some extra operation based on the result of aggregate function. Finally I've found some solution for aggregate function and the operation based on the result in MongoDB. I've a collection Request with field request, source, status...
Possible to do a MySQL foreign key to one of two possible tables?
... do take advantage of database-enforced referential integrity:
Create one extra table per target. For example popular_states and popular_countries, which reference states and countries respectively. Each of these "popular" tables also reference the user's profile.
CREATE TABLE popular_states (
...
Red black tree over avl tree
...ack tree.
AVL trees store the balance factor at each node. This takes O(N) extra space. However, if we know that the keys that will be inserted in the tree will always be greater than zero, we can use the sign bit of the keys to store the colour information of a red-black tree. Thus, in such cases r...
Find index of last occurrence of a sub-string using T-SQL
...ere a straightforward way of finding the index of the last occurrence of a string using SQL? I am using SQL Server 2000 right now. I basically need the functionality that the .NET System.String.LastIndexOf method provides. A little googling revealed this - Function To Retrieve Last Index - bu...
How to put a new line into a wpf TextBlock control?
...
baz bar</data>
If that does not work you might need to parse the string manually.
If you need direct XAML that's easy by the way:
<TextBlock>
Lorem <LineBreak/>
Ipsum
</TextBlock>
share...
Emulate a do-while loop in Python?
...lso, is this real code where you are processing comments? What if you have strings with slashes? ie: print "blah // <-- does that mess you up?"
– Tom
Apr 13 '09 at 7:44
4
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How do I create a comma-separated list from an array in PHP?
...r if you want to manipulate that data in the array before making it into a string; For example, addslashes, or mysql_real_escape_string.
– Naphtali Gilead
Aug 21 '15 at 15:48
...
Return positions of a regex match() in Javascript?
Is there a way to retrieve the (starting) character positions inside a string of the results of a regex match() in Javascript?
...
How do you embed binary data in XML?
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If you're using .NET, you can convert a binary file directly to a base64 string and stick it inside an XML element.
string base64 = Convert.ToBase64String(File.ReadAllBytes(fileName));
Or, there is a method built right into the XmlWriter object. In my particular case, I had to include Microsoft...