llJsonGetValue

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Summary

Function: string llJsonGetValue( string json, list specifiers );
0.0 Forced Delay
10.0 Energy

Gets the value indicated by specifiers from the json string.
Returns a string made by parsing json, a string representing json and traversing as specified by specifiers.

• string json
• list specifiers

When the input is invalid or no result can be found this function returns JSON_INVALID. If the result is null the function returns JSON_NULL.

Specification

Examples

<lsl> JGetValTest(){

   string j="[[1,2],[4,5,6]]";            //JSON may be written directly as a string like this in sl.
   string k;                              //this will change with each command below;
   k=llJsonGetValue(j,[]);                //returns the whole array of a JSON. It might just be one entry or a whole nested array or whole nested object.
   //if "j" is a single JSON_STRING, this may return what the string represents as a JSON within a string; a JSON_NUMBER , JSON_TRUE, TRUE ...
   k=llJsonGetValue("\"3.14\"",[]);       //==k="3,14" (float that was stored in a JSON_STRING within a JSON. and not as JSON_NUMBER for no good reason)
   k=llJsonGetValue("\"TRUE\""     ,[]);  //==k="TRUE" (the value was stored as a JSON_STRING and is thus returned verbatim)
   k=llJsonGetValue(j,[0]);               //returns only the first entry (at offset 0). An entry can be any JSON type,
                                          //each entry being separated by a comma from other entries.
                                          //array and object entries may contain multiple comma separated entries within them.
   k=llJsonGetValue(j,[1]);//returns only the second entry... (all the above still applies) k="[4,5,6]";
   k=llJsonGetValue(llJsonGetValue(j,[1]),[2]);
                                          //instead of getting an entry from "j" we get a sub-entry from llJsonGetValue(j,[1]), 
                                          //assuming the sub-entry is a JSON_ARRAY. It returns the 3rd sub-entry of the second entry, 
                                          //that is an array with 3 entries. it would make k="6". 
                                          //it will return JSON_INVALID if there is no 3rd entry in the 2nd sub-array,
                                          //or not 2nd sub-array.
   k=llJsonGetValue(j,[1,2]);             //Shorter way to do the same as in the previous example.
   k=llJsonGetValue("true",[]);           //Sets k to JSON_TRUE
   k=llJsonGetValue("True",[]);           //Sets k to JSON_INVALID because the JSON constant for 'true' is all lower case
   k=llJsonGetValue("TRUE",[]);           //Sets k to JSON_INVALID because the JSON constant for 'true' is all lower case

} </lsl>

See also llJsonValueType for examples where the value type is checked before getting the value as that type.

See Also

Functions

•  llList2Json
•  llJson2List
•  llJsonSetValue
•  llJsonValueType

Articles

•  Typecast

Deep Notes

History

Date of Release 20/05/2013

Signature

function string llJsonGetValue( string json, list specifiers );