json/doc/mkdocs/docs/api/basic_json/dump.md
2020-07-27 14:07:13 +02:00

74 lines
2 KiB
Markdown

# basic_json::dump
```cpp
string_t dump(const int indent = -1,
const char indent_char = ' ',
const bool ensure_ascii = false,
const error_handler_t error_handler = error_handler_t::strict) const
```
Serialization function for JSON values. The function tries to mimic
Python's `json.dumps()` function, and currently supports its `indent`
and `ensure_ascii` parameters.
## Parameters
`indent` (in)
: If `indent` is nonnegative, then array elements and object
members will be pretty-printed with that indent level. An indent level of
`0` will only insert newlines. `-1` (the default) selects the most compact
representation.
`indent_char` (in)
: The character to use for indentation if `indent` is
greater than `0`. The default is ` ` (space).
`ensure_ascii` (in)
: If `ensure_ascii` is true, all non-ASCII characters
in the output are escaped with `\uXXXX` sequences, and the result consists
of ASCII characters only.
`error_handler` (in)
: how to react on decoding errors; there are three
possible values: `strict` (throws and exception in case a decoding error
occurs; default), `replace` (replace invalid UTF-8 sequences with U+FFFD),
and `ignore` (ignore invalid UTF-8 sequences during serialization; all
bytes are copied to the output unchanged).
## Return value
string containing the serialization of the JSON value
## Exception safety
Strong guarantee: if an exception is thrown, there are no
changes to any JSON value.
## Complexity
Linear.
## Notes
Binary values are serialized as object containing two keys:
- "bytes": an array of bytes as integers
- "subtype": the subtype as integer or `#!json null` if the binary has no subtype
## Example
??? example
The following example shows the effect of different `indent`,
`indent_char`, and `ensure_ascii` parameters to the result of the
serialization.
```cpp
--8<-- "examples/dump.cpp"
```
Output:
```json
--8<-- "examples/dump.output"
```