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What is the easiest/best/most correct way to iterate through the characters of a string in Java?
StringTokenizer ? Convert the String to a char[] and iterate over that? Something else?
15 Answers
...
Pointer expressions: *ptr++, *++ptr and ++*ptr
...ith your program, as it's the simplest to explain.
int main()
{
const char *p = "Hello";
while(*p++)
printf("%c",*p);
return 0;
}
The first statement:
const char* p = "Hello";
declares p as a pointer to char. When we say "pointer to a char", what does that mean? It means th...
Creating C formatted strings (not printing them)
...
Use sprintf.
int sprintf ( char * str, const char * format, ... );
Write formatted data to string Composes a string with the same text
that would be printed if format was used on printf, but instead of
being printed, the content is stored as a C stri...
strdup() - what does it do in C?
...'s a POSIX thing), it's effectively doing the same as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (src) + 1); // Space for length plus nul
if (dst == NULL) return NULL; // No memory
strcpy(dst, src); // Copy the characters...
BestPractice - Transform first character of a string into lower case
I'd like to have a method that transforms the first character of a string into lower case.
11 Answers
...
What function is to replace a substring from a string in C?
Given a ( char * ) string, I want to find all occurrences of a substring and replace them with an alternate string. I do not see any simple function that achieves this in <string.h> .
...
Which MySQL datatype to use for an IP address? [duplicate]
...nvert them:
INSERT INTO `table` (`ipv4`) VALUES (INET_ATON("127.0.0.1"));
SELECT INET_NTOA(`ipv4`) FROM `table`;
For IPv6 addresses you could use a BINARY instead:
`ipv6` BINARY(16)
And use PHP’s inet_pton and inet_ntop for conversion:
'INSERT INTO `table` (`ipv6`) VALUES ("'.mysqli_real_es...
Example JavaScript code to parse CSV data
...= $.csv.toArrays(csv, {
delimiter: "'", // Sets a custom value delimiter character
separator: ';', // Sets a custom field separator character
});
Update 2:
It now works with jQuery on Node.js too. So you have the option of doing either client-side or server-side parsing with the same library.
U...
Get an object properties list in Objective-C
...nt; i++) {
objc_property_t property = properties[i];
const char *propName = property_getName(property);
if(propName) {
const char *propType = getPropertyType(property);
NSString *propertyName = [NSString stringWithCString:propName
...
NULL values inside NOT IN clause
...
Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <&...