json_filter Function

Syntax

C result = json_filter(json as C[, propertyNames as C [, exclude as L ]] )

Arguments

jsonCharacter: input string of JSON data
propertyNamesCharacter: comma delimited list of the property names in the JSON string that you want to filter.
excludeLogical: .t. or .f. - default .f. - if exclude = .t. the specified property Names are excluded from the JSON string

Description

The json_filter() Function - Extracts or omits certain properties from a JSON string. NOTE: Conceptually, this function is similar to the filter_string() function, except that it operates on JSON strings.

Example

'extract object with a single field
dim json as c 
json = <<%txt%
{
    "one" : 1 , 
    "two" : "TWO" , 
    "three" : [ 1 ,2 ,3 ]
}
%txt%

? json_filter(json,"one")
= {  "one" : 1}


? json_filter(json,"two")
= {  "two" : "TWO"}

? json_filter(json,"three")
= {  "three" : [ 1 ,2 ,3 ]}

'exclude a single field
? json_filter(json,"one",.t.)
= {  "two" : "TWO" , "three" : [ 1 ,2 ,3 ]}


? json_filter(json,"two",.t.)
= {  "one" : 1 , "three" : [ 1 ,2 ,3 ]}

? json_filter(json,"three",.t.)
= {  "one" : 1 , "two" : "TWO"}


'include multiple (comma separated) fields
? json_filter(json,"one,two")
= {  "one" : 1 , "two" : "TWO"}

? json_filter(json,"one,three")
= {  "one" : 1 , "three" : [ 1 ,2 ,3 ]}