Json::StreamWriterBuilder Class Reference

Build a StreamWriter implementation. More...

#include <json/writer.h>

Inherits Json::StreamWriter::Factory.

Public Member Functions
	StreamWriterBuilder ()
	~StreamWriterBuilder () override
StreamWriter *	newStreamWriter () const override
bool	validate (Json::Value *invalid) const
Value &	operator[] (const String &key)
	A simple way to update a specific setting. More...
Public Member Functions inherited from Json::StreamWriter::Factory
virtual	~Factory ()

Static Public Member Functions
static void	setDefaults (Json::Value *settings)
	Called by ctor, but you can use this to reset settings_. More...

Public Attributes
Json::Value	settings_
	Configuration of this builder. More...

Detailed Description

Build a StreamWriter implementation.

Usage:

using namespace Json;
Value value = ...;
StreamWriterBuilder builder;
builder["commentStyle"] = "None";
builder["indentation"] = "   ";  // or whatever you like
std::unique_ptr<Json::StreamWriter> writer(
   builder.newStreamWriter());
writer->write(value, &std::cout);
std::cout << std::endl;  // add lf and flush

Constructor & Destructor Documentation

StreamWriterBuilder()

Json::StreamWriterBuilder::StreamWriterBuilder

(

)

~StreamWriterBuilder()

Json::StreamWriterBuilder::~StreamWriterBuilder ( )

overridedefault

Member Function Documentation

newStreamWriter()

StreamWriter * Json::StreamWriterBuilder::newStreamWriter ( ) const

overridevirtual

Exceptions

std::exception

if something goes wrong (e.g. invalid settings)

Implements Json::StreamWriter::Factory.

operator[]()

Value & Json::StreamWriterBuilder::operator[]

(

const String &

key

)

A simple way to update a specific setting.

setDefaults()

void Json::StreamWriterBuilder::setDefaults ( Json::Value *  settings )

static

Called by ctor, but you can use this to reset settings_.

Precondition

'settings' != NULL (but Json::null is fine)

Remarks

Defaults:

  (*settings)["commentStyle"] = "All";
  (*settings)["indentation"] = "\t";
  (*settings)["enableYAMLCompatibility"] = false;
  (*settings)["dropNullPlaceholders"] = false;
  (*settings)["useSpecialFloats"] = false;
  (*settings)["emitUTF8"] = false;
  (*settings)["precision"] = 17;
  (*settings)["precisionType"] = "significant";

[StreamWriterBuilderDefaults]

[StreamWriterBuilderDefaults]

validate()

bool Json::StreamWriterBuilder::validate

(

Json::Value *

invalid

)

const

Returns

true if 'settings' are legal and consistent; otherwise, indicate bad settings via 'invalid'.

Member Data Documentation

settings_

Json::Value Json::StreamWriterBuilder::settings_

Configuration of this builder.

Available settings (case-sensitive):

• "commentStyle": "None" or "All"
• "indentation": "<anything>".
• Setting this to an empty string also omits newline characters.
• "enableYAMLCompatibility": false or true
• slightly change the whitespace around colons
• "dropNullPlaceholders": false or true
• Drop the "null" string from the writer's output for nullValues. Strictly speaking, this is not valid JSON. But when the output is being fed to a browser's JavaScript, it makes for smaller output and the browser can handle the output just fine.
• "useSpecialFloats": false or true
• If true, outputs non-finite floating point values in the following way: NaN values as "NaN", positive infinity as "Infinity", and negative infinity as "-Infinity".
• "precision": int
• Number of precision digits for formatting of real values.
• "precisionType": "significant"(default) or "decimal"
• Type of precision for formatting of real values.

You can examine 'settings_` yourself to see the defaults. You can also write and read them just like any JSON Value.

See also

setDefaults()

---

The documentation for this class was generated from the following files:

• include/json/writer.h
• src/lib_json/json_writer.cpp