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### jsoncons::basic_json_encoder
```cpp
#include <jsoncons/json_encoder.hpp>
template<
typename CharT,
typename Sink>
> basic_json_encoder : public jsoncons::basic_json_visitor<CharT>
template<
typename CharT,
typename Sink>
> basic_compact_json_encoder : public jsoncons::basic_json_visitor<CharT>
```
`basic_json_encoder` and `basic_compact_json_encoder` are noncopyable and nonmoveable.

Four specializations for common character types and sink types are defined
for both the pretty print and compressed serializers:
Type |Definition
---------------------------|------------------------------
json_stream_encoder |basic_json_encoder<char,jsoncons::stream_sink<char>>
json_string_encoder |basic_json_encoder<char,jsoncons::string_sink<std::string>>
wjson_stream_encoder |basic_json_encoder<wchar_t,jsoncons::stream_sink<wchar_t>>
wjson_string_encoder |basic_json_encoder<wchar_t,jsoncons::string_sink<std::wstring>>
compact_json_stream_encoder (since 0.151.2) |basic_compact_json_encoder<char,jsoncons::stream_sink<char>>
compact_json_string_encoder (since 0.151.2) |basic_compact_json_encoder<char,jsoncons::string_sink<std::string>>
compact_wjson_stream_encoder (since 0.151.2) |basic_compact_json_encoder<wchar_t,jsoncons::stream_sink<wchar_t>>
compact_wjson_string_encoder (since 0.151.2) |basic_compact_json_encoder<wchar_t,jsoncons::string_sink<std::wstring>>
#### Member types
Type |Definition
---------------------------|------------------------------
char_type |CharT
sink_type |Sink
string_view_type |
#### Constructors
explicit basic_json_encoder(Sink&& sink)
Constructs a new encoder that is associated with the destination `sink`.
basic_json_encoder(Sink&& sink,
const basic_json_options<CharT>& options)
Constructs a new encoder that is associated with the destination `sink`
and uses the specified [json options](basic_json_options.md).
#### Destructor
virtual ~basic_json_encoder() noexcept
#### Member functions
void reset();
Reset encoder to write another value to the same sink
void reset(Sink&& sink)
Reset encoder to write a new value to a new sink
#### Inherited from [basic_json_visitor](../basic_json_visitor.md)
void flush(); (1)
bool begin_object(semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (2)
bool begin_object(std::size_t length,
semantic_tag tag=semantic_tag::none,
const ser_context& context = ser_context()); (3)
bool end_object(const ser_context& context = ser_context()); (4)
bool begin_array(semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (5)
bool begin_array(std::size_t length,
semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (6)
bool end_array(const ser_context& context=ser_context()); (7)
bool key(const string_view_type& name,
const ser_context& context=ser_context()); (8)
bool null_value(semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (9)
bool bool_value(bool value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (10)
bool string_value(const string_view_type& value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (11)
bool byte_string_value(const byte_string_view& source,
semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (12) (until 0.152.0)
template <typename ByteStringLike>
bool byte_string_value(const ByteStringLike& souce,
semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (12) (since 0.152.0)
template <typename ByteStringLike>
bool byte_string_value(const ByteStringLike& souce,
uint64_t ext_tag,
const ser_context& context=ser_context()); (13) (since 0.152.0)
bool uint64_value(uint64_t value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (14)
bool int64_value(int64_t value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (15)
bool half_value(uint16_t value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (16)
bool double_value(double value,
semantic_tag tag = semantic_tag::none,
const ser_context& context=ser_context()); (17)
bool begin_object(semantic_tag tag,
const ser_context& context,
std::error_code& ec); (18)
bool begin_object(std::size_t length,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (19)
bool end_object(const ser_context& context,
std::error_code& ec); (20)
bool begin_array(semantic_tag tag,
const ser_context& context,
std::error_code& ec); (21)
bool begin_array(std::size_t length,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (22)
bool end_array(const ser_context& context,
std::error_code& ec); (23)
bool key(const string_view_type& name,
const ser_context& context,
std::error_code& ec); (24)
bool null_value(semantic_tag tag,
const ser_context& context,
std::error_code& ec); (25)
bool bool_value(bool value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (26)
bool string_value(const string_view_type& value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (27)
bool byte_string_value(const byte_string_view& source,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (28) (until 0.152.0)
template <typename ByteStringLike>
bool byte_string_value(const ByteStringLike& source,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (28) (since 0.152.0)
template <typename ByteStringLike>
bool byte_string_value(const ByteStringLike& source,
uint64_t ext_tag,
const ser_context& context,
std::error_code& ec); (29) (since 0.152.0)
bool uint64_value(uint64_t value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (30)
bool int64_value(int64_t value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (31)
bool half_value(uint16_t value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (32)
bool double_value(double value,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (33)
template <typename T>
bool typed_array(const span<T>& data,
semantic_tag tag=semantic_tag::none,
const ser_context& context=ser_context()); (34)
bool typed_array(half_arg_t, const span<const uint16_t>& s,
semantic_tag tag = semantic_tag::none,
const ser_context& context = ser_context()); (35)
bool begin_multi_dim(const span<const size_t>& shape,
semantic_tag tag,
const ser_context& context); (36)
bool end_multi_dim(const ser_context& context=ser_context()); (37)
template <typename T>
bool typed_array(const span<T>& data,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (38)
bool typed_array(half_arg_t, const span<const uint16_t>& s,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (39)
bool begin_multi_dim(const span<const size_t>& shape,
semantic_tag tag,
const ser_context& context,
std::error_code& ec); (40)
bool end_multi_dim(const ser_context& context,
std::error_code& ec); (41)
(1) Flushes whatever is buffered to the destination.
(2) Indicates the begining of an object of indefinite length.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(3) Indicates the begining of an object of known length.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(4) Indicates the end of an object.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(5) Indicates the beginning of an indefinite length array.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(6) Indicates the beginning of an array of known length.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(7) Indicates the end of an array.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(8) Writes the name part of an object name-value pair.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(9) Writes a null value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(10) Writes a boolean value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(11) Writes a text string value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(12) Writes a byte string value `source` with a generic tag.
Type `ByteStringLike` must be a container that has member functions `data()` and `size()`,
and member type `value_type` with size exactly 8 bits (since 0.152.0.)
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(13) Writes a byte string value `source` with a format specific tag, `ext_tag`.
Type `ByteStringLike` must be a container that has member functions `data()` and `size()`,
and member type `value_type` with size exactly 8 bits (since 0.152.0.)
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(14) Writes a non-negative integer value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(15) Writes a signed integer value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(16) Writes a half precision floating point value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(17) Writes a double precision floating point value.
Returns `true` if the consumer wishes to receive more events, `false` otherwise.
Throws a [ser_error](ser_error.md) on parse errors.
(18)-(33) Same as (2)-(17), except sets `ec` and returns `false` on parse errors.
### Examples
### Feeding json events directly to a `json_stream_encoder`
```cpp
#include <iostream>
#include <boost/numeric/ublas/matrix.hpp>
#include <jsoncons/json_encoder.hpp>
using namespace jsoncons;
using boost::numeric::ublas::matrix;
int main()
{
matrix<double> A(2, 2);
A(0, 0) = 1;
A(0, 1) = 2;
A(1, 0) = 3;
A(1, 1) = 4;
auto options = json_options{};
json_stream_encoder os(std::cout, options);
os.begin_array();
for (std::size_t i = 0; i < A.size1(); ++i)
{
os.begin_array();
for (std::size_t j = 0; j < A.size2(); ++j)
{
os.double_value(A(i, j));
}
os.end_array();
}
os.end_array();
return 0;
}
```
Output:
```json
[
[1,2],
[3,4]
]
```
### See also
[byte_string_view](../byte_string_view.md)
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