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IEnumerable to string [duplicate]
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You can use String.Concat().
var allowedString = String.Concat(
inputString.Where(c => allowedChars.Contains(c))
);
Caveat: This approach will have some performance implications. String.Concat doesn't special case collections of char...
Best practices/performance: mixing StringBuilder.append with String.concat
I'm trying to understand what the best practice is and why for concatenating string literals and variables for different cases. For instance, if I have code like this
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How to remove leading and trailing whitespace in a MySQL field?
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I downvoted. Testcase: SELECT CONCAT('"', TRIM(" hello world "), '"') AS `trimmed value` FROM DUAL gives the wanted output "hello world". While the replace variant dangerously removes the space as word separator: SELECT CONCAT('"', REPLACE(" hello world "...
How do I concatenate two strings in C?
...of char that is terminated by the first null character. There is no string concatenation operator in C.
Use strcat to concatenate two strings. You could use the following function to do it:
#include <stdlib.h>
#include <string.h>
char* concat(const char *s1, const char *s2)
{
char...
Cast int to varchar
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@Pacerier IMO, using concat() to do a conversion isn't necessarily that intuitive. I'd prefer my code to be clear and that just doesn't make a whole lot of sense.
– Taryn♦
Apr 8 '15 at 12:19
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byte[] to hex string [duplicate]
...verting bytes to a string would be so much slower. You weren't using += to concatenate the strings together, were you?
– Guffa
Nov 23 '15 at 22:29
4
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Is there an easy way to return a string repeated X number of times?
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If you're using .NET 4.0, you could use string.Concat together with Enumerable.Repeat.
int N = 5; // or whatever
Console.WriteLine(string.Concat(Enumerable.Repeat(indent, N)));
Otherwise I'd go with something like Adam's answer.
The reason I generally wouldn't advise ...
String concatenation: concat() vs “+” operator
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Firstly, there's a slight difference in semantics. If a is null, then a.concat(b) throws a NullPointerException but a+=b will treat the original value of a as if it were null. Furthermore, the concat() method only accepts String values while the + operator will silently convert the argument to a ...
Best way to repeat a character in C#
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string.Concat(Enumerable.Repeat("ab", 2));
Returns
"abab"
And
string.Concat(Enumerable.Repeat("a", 2));
Returns
"aa"
from...
Is there a built-in function to repeat string or char in .net?
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Capitalize first letter. MySQL
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It's almost the same, you just have to change to use the CONCAT() function instead of the + operator :
UPDATE tb_Company
SET CompanyIndustry = CONCAT(UCASE(LEFT(CompanyIndustry, 1)),
SUBSTRING(CompanyIndustry, 2));
This would turn hello to Hello, wO...