The lookupByPath
method returns the value at the specified path in the JSON array.
This method does not make a copy of the value, so modifying the returned value affects the original object.
lookupByPath( path )
Argument | Description |
---|---|
path
|
(string) The path of the value to return. 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. |
(LuaJsonValue) Returns the value that exists at the specified path, or nil
if the specified path does not exist.
local myJsonObject = LuaJsonObject:new() myJsonObject:assign( { attr1=LuaJsonObject:new( { n=42, x=5 } ), attr2=LuaJsonArray:new( 1, 2, "three" ), } ) local myJsonValue = LuaJsonValue:new( myJsonObject ) print ( myJsonValue:lookupByPath("attr2/2"):value() ) -- three (LuaJsonArrays are zero-indexed) -- Modifying the returned value changes the original object local lookup = myJsonValue:lookupByPath("attr1"):object() lookup:assign("y",3) print (myJsonValue:string()) -- {"attr1":{"n":42,"x":5,"y":3},"attr2":[1,2,"three"]}
|