public member function
<string>

std::string::length

size_t length() const;

size_t length() const noexcept;
Return length of string
Returns the length of the string, in terms of bytes.

This is the number of actual bytes that conform the contents of the string, which is not necessarily equal to its storage capacity.

Note that string objects handle bytes without knowledge of the encoding that may eventually be used to encode the characters it contains. Therefore, the value returned may not correspond to the actual number of encoded characters in sequences of multi-byte or variable-length characters (such as UTF-8).

Both string::size and string::length are synonyms and return the exact same value.

Parameters

none

Return Value

The number of bytes in the string.

size_t is an unsigned integral type (the same as member type string::size_type).

Example

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// string::length
#include <iostream>
#include <string>

int main ()
{
  std::string str ("Test string");
  std::cout << "The size of str is " << str.length() << " bytes.\n";
  return 0;
}


Output:
The size of str is 11 bytes

Complexity

Unspecified.
Constant.

Iterator validity

No changes.

Data races

The object is accessed.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also

string::size
Return length of string (public member function )
string::resize
Resize string (public member function )
string::max_size
Return maximum size of string (public member function )
string::capacity
Return size of allocated storage (public member function )

C++