Return the number of bytes needed to store a string with percent-encoding applied.

Synopsis

Defined in header <boost/url/encode.hpp>

template<
    class CharSet = grammar::all_chars_t>
std::size_t
encoded_size(
    string_view s,
    encode_opts const& opt = {},
    CharSet const& allowed = {});

Description

This function examines the characters in the string to determine the number of bytes necessary if the string were to be percent encoded using the given options and character set. No encoding is actually performed.

Example 1

Find the number of bytes needed to encode a string without transforming ' ' to '+'.

encode_opts opt;
opt.space_to_plus = false;
std::size_t n = encoded_size( "My Stuff", pchars, opt );

assert( n == 10 );

Example 2

Find the number of bytes needed to encode a string when transforming ' ' to '+'.

encode_opts opt;
opt.space_to_plus = true;
std::size_t n = encoded_size( "My Stuff", opt, pchars );

assert( n == 8 );

Exception Safety

Throws nothing.

Return Value

The number of bytes needed, excluding any null terminator.

Parameters

Specification

See Also

decode, encode, encode_opts.

Convenience header <boost/url.hpp>