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Check if list is empty in C# [closed]
I have a list of objects populated from a database. I need to display an error message if the list is empty and display a grid view otherwise.
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Why are dashes preferred for CSS selectors / HTML attributes?
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Code completion
Whether dash is interpreted as punctuation or as an opaque identifier depends on the editor of choice, I guess. However, as a personal preference, I favor being able to tab between each word in a CSS file and would find it annoying if the...
What does it mean by select 1 from table?
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SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, common enough to be noted, even if it isn't really meaningful (...
Reorder levels of a factor without changing order of values
...some categorical factor variables. The order of levels for those factors is not the way I want them to be.
7 Answers
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How to serialize an object into a string
I am able to serialize an object into a file and then restore it again as is shown in the next code snippet. I would like to serialize the object into a string and store into a database instead. Can anyone help me?
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How to construct a timedelta object from a simple string
...st enter something like "32m" or "2h32m", or even "4:13" or "5hr34m56s"... Is there a library or something that has this sort of thing already implemented?
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'Incomplete final line' warning when trying to read a .csv file into R
I'm trying to read a .csv file into R and upon using this formula:
15 Answers
15
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Why can't I use switch statement on a String?
Is this functionality going to be put into a later Java version?
16 Answers
16
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I want to remove double quotes from a String
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Assuming:
var someStr = 'He said "Hello, my name is Foo"';
console.log(someStr.replace(/['"]+/g, ''));
That should do the trick... (if your goal is to replace all double quotes).
Here's how it works:
['"] is a character class, matches both single and double quotes. you...
Why does C# allow {} code blocks without a preceding statement?
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In the context you give, there is no significance. Writing a constant string to the console is going to work the same way anywhere in program flow.1
Instead, you typically use them to restrict the scope of some local variables. This is further elaborated ...