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How do I find out if first character of a string is a number?
In Java is there a way to find out if first character of a string is a number?
5 Answers
...
How does database indexing work? [closed]
... Size on disk
id (Primary key) Unsigned INT 4 bytes
firstName Char(50) 50 bytes
lastName Char(50) 50 bytes
emailAddress Char(100) 100 bytes
Note: char was used in place of varchar to allow for an accurate size on disk value.
This sample database contains ...
Concatenate strings in Less
...e it was changing my background-image url, and I wasn't too sure how to do concatenation :)
– hatsrumandcode
Dec 22 '15 at 16:18
7
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SQL query to group by day
...er (from Jon Bright):
GROUP BY date(datefield)
For Oracle:
GROUP BY to_char(datefield, 'yyyy-mm-dd')
or faster (from IronGoofy):
GROUP BY trunc(created);
For Informix (by Jonathan Leffler):
GROUP BY date_column
GROUP BY EXTEND(datetime_column, YEAR TO DAY)
...
UTF-8 byte[] to String
...Look at the constructor for String
String str = new String(bytes, StandardCharsets.UTF_8);
And if you're feeling lazy, you can use the Apache Commons IO library to convert the InputStream to a String directly:
String str = IOUtils.toString(inputStream, StandardCharsets.UTF_8);
...
Can a C++ enum class have methods?
... mouse_event_middle_up,
mouse_event_wheel
};
static const char* ToStr (const type::LowLevelMouseEvent::Enum& event)
{
switch (event) {
case mouse_event_unknown: return "unknown";
case mouse_event_unimplemented: return "unimplemented"...
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
......
}
}
const_cast :
// *Passwd declared as a const
const unsigned char *Passwd
// on some situation it require to remove its constness
const_cast<unsigned char*>(Passwd)
reinterpret_cast :
typedef unsigned short uint16;
// Read Bytes returns that 2 bytes got read.
bool ByteBu...
How to detect READ_COMMITTED_SNAPSHOT is enabled?
...null_dflt_on SET
ansi_warnings SET
ansi_padding SET
ansi_nulls SET
concat_null_yields_null SET
isolation level read committed
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Why doesn't this work List<Character> word1 = new ArrayList<Character>(Arrays.asList(A[0].toCharArray())); I'm trying to get first String of an string array, and convert that string into charArray and that charArray to List<Character>
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Replace non-numeric with empty string
...project. A field in our DB to hold a phone number is set to only allow 10 characters. So, if I get passed "(913)-444-5555" or anything else, is there a quick way to run a string through some kind of special replace function that I can pass it a set of characters to allow?
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