Difference between revisions of "Json parser and writer"
From VCMI Project Wiki
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const JsonNode node("some_config.json"); | const JsonNode node("some_config.json"); | ||
std::string value = node["value"].String(); | std::string value = node["value"].String(); | ||
| + | </syntaxhighlight> | ||
| + | |||
| + | Note: accessing not present in JSON fields is legal and returns correctly initialized default value. There is no need for any checks for entry presence. | ||
| + | Good: | ||
| + | <syntaxhighlight lang="cpp"> | ||
| + | int someField = config["someField"].Float(); | ||
| + | <someField correctly initialized> | ||
| + | </syntaxhighlight> | ||
| + | Bad: | ||
| + | <syntaxhighlight lang="cpp"> | ||
| + | int someField; | ||
| + | if (config["someField"].isNull()) | ||
| + | someField = config["someField"].Float(); | ||
| + | else | ||
| + | someField = 0; | ||
| + | <someField correctly initialized> | ||
</syntaxhighlight> | </syntaxhighlight> | ||
Revision as of 17:43, 14 March 2013
Capable of error checking and basic error recovery. Also have optional schema validation. Located at lib/JsonNode.h. Currently supports only local encoding - no conversion from unicode.
Main class JsonNode represents one "node" from Json file (array, string, etc.). Basic usage:
const JsonNode node("some_config.json");
std::string value = node["value"].String();
Note: accessing not present in JSON fields is legal and returns correctly initialized default value. There is no need for any checks for entry presence. Good:
int someField = config["someField"].Float();
<someField correctly initialized>
Bad:
int someField;
if (config["someField"].isNull())
someField = config["someField"].Float();
else
someField = 0;
<someField correctly initialized>
