| Localization library | |||||||||||||||||||||||||
| Regular expressions library(C++11) | |||||||||||||||||||||||||
| Formatting library(C++20) | |||||||||||||||||||||||||
| Null-terminated sequence utilities | |||||||||||||||||||||||||
| Byte strings | |||||||||||||||||||||||||
| Multibyte strings | |||||||||||||||||||||||||
| Wide strings | |||||||||||||||||||||||||
| Primitive numeric conversions | |||||||||||||||||||||||||
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| Text encoding identifications | |||||||||||||||||||||||||
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| Functions | ||||||||||||||||||||||||||||||||||||
| Character classification | ||||||||||||||||||||||||||||||||||||
| Character manipulation | ||||||||||||||||||||||||||||||||||||
| Conversions to numeric formats | ||||||||||||||||||||||||||||||||||||
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| String manipulation | ||||||||||||||||||||||||||||||||||||
| String examination | ||||||||||||||||||||||||||||||||||||
| Character array functions | ||||||||||||||||||||||||||||||||||||
| Miscellaneous | ||||||||||||||||||||||||||||||||||||
Defined in header <cstring> | ||
std::size_t strcspn(constchar*dest,constchar*src); | ||
Returns the length of the maximum initial segment of the byte string pointed to bydest, that consists of only the charactersnot found in byte string pointed to bysrc.
The function name stands for "complementary span".
Contents |
| dest | - | pointer to the null-terminated byte string to be analyzed |
| src | - | pointer to the null-terminated byte string that contains the characters to search for |
The length of the maximum initial segment that contains only characters not found in the byte string pointed to bysrc.
#include <cstddef>#include <cstring>#include <iomanip>#include <iostream>#include <string> int main(){std::string s="abcde312$#@";constchar* invalid="*$#"; conststd::size_t valid_len= std::strcspn(s.c_str(), invalid);if(valid_len!= s.size()){std::cout<<std::quoted(s)<<" contains invalid chars starting at position "<< valid_len<<'\n'<<std::string(valid_len+1,'-')<<"^\n";}}
Output:
"abcde312$#@" contains invalid chars starting at position 8---------^
| returns the length of the maximum initial segment that consists of only the characters found in another byte string (function)[edit] | |
| returns the length of the maximum initial segment that consists of only the widenot found in another wide string (function)[edit] | |
| finds the first location of any character from a set of separators (function)[edit] | |
| find first occurrence of characters (public member function of std::basic_string<CharT,Traits,Allocator>)[edit] | |
C documentation forstrcspn | |
