existsByPath
The existsByPath
method checks whether a specified path exists in the JSON value.
Syntax
existsByPath( path )
Arguments
Argument | Description |
---|---|
path
|
(string) The path to check. Construct the path from array indexes and object attribute names, and use a slash (/ ) as the separator. If an object attribute name includes a slash, then escape the slash with a backslash, for example "one\\/two" . Notice that you must also escape a backslash with another backslash. |
Returns
(Boolean) Returns true
if the path exists, false
otherwise.
Example
Consider the following JSON:
{ "product": "IDOL", "component": "CFS", "version": { "major": 11, "minor": 3 }, "ports": [ { "type": "ACI", "number": 7000 }, { "type": "Service", "number": 17000 } ] }
If this JSON is represented by a LuaJsonValue
object named myJsonValue
, you could use the existsByPath
method as follows:
print (myJsonValue:existsByPath("ports/0/type")) -- true (LuaJsonArrays are zero-indexed) print (myJsonValue:existsByPath("ports/2/type") ) -- false (LuaJsonArrays are zero-indexed, and there is no third value) print (myJsonValue:existsByPath("version/major")) -- true