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The term descendant is intentional because you can extract members or entities deep within the JSON tree in a single call. Let's use the following JSON as an example:
| Code Block |
|---|
{"menu": {
"header": "SVG Viewer",
"items": [
{"id": "Open"},
{"id": "OpenNew", "label": "Open New"},
null,
{"id": "ZoomIn", "label": "Zoom In"},
{"id": "ZoomOut", "label": "Zoom Out"},
{"id": "OriginalView", "label": "Original View"},
null,
{"id": "Quality"},
{"id": "Pause"},
{"id": "Mute"},
null,
{"id": "Find", "label": "Find..."},
{"id": "FindAgain", "label": "Find Again"},
{"id": "Copy"},
{"id": "CopyAgain", "label": "Copy Again"},
{"id": "CopySVG", "label": "Copy SVG"},
{"id": "ViewSVG", "label": "View SVG"},
{"id": "ViewSource", "label": "View Source"},
{"id": "SaveAs", "label": "Save As"},
null,
{"id": "Help"},
{"id": "About", "label": "About Adobe CVG Viewer..."}
]
}} |
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In this example, we have a root object with a single child object called "menu" as it's only member. That object contains a member called items, which is an array, and each element in the array is either null or a child object. As you can see, it would be cumbersome to extract a single descendant as it would require getting a child handle, followed by another child handle, and so on. That is why the GET service supports a path.
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LabelHandle = SRP_JSON(ObjectHandle, "GET", "menu.items[2].label") |
| Note |
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| This service always returns a JSON Entity Handle. If you know the descendant will be a String, Number, or Boolean type entity, you might prefer to use GETVALUE instead, which gets the value instead of the handle. |
Example
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// Test parsing an existing JSON string and then drilling down into specific values
SampleJSON = '{"menu": {'
SampleJSON := ' "header": "SVG Viewer",'
SampleJSON := ' "items": ['
SampleJSON := ' {"id": "Open"},'
SampleJSON := ' {"id": "OpenNew", "label": "Open New"},'
SampleJSON := ' null,'
SampleJSON := ' {"id": "ZoomIn", "label": "Zoom In"},'
SampleJSON := ' {"id": "ZoomOut", "label": "Zoom Out"},'
SampleJSON := ' {"id": "OriginalView", "label": "Original View"},'
SampleJSON := ' null,'
SampleJSON := ' {"id": "Quality"},'
SampleJSON := ' {"id": "Pause"},'
SampleJSON := ' {"id": "Mute"},'
SampleJSON := ' null,'
SampleJSON := ' {"id": "Find", "label": "Find..."},'
SampleJSON := ' {"id": "FindAgain", "label": "Find Again"},'
SampleJSON := ' {"id": "Copy"},'
SampleJSON := ' {"id": "CopyAgain", "label": "Copy Again"},'
SampleJSON := ' {"id": "CopySVG", "label": "Copy SVG"},'
SampleJSON := ' {"id": "ViewSVG", "label": "View SVG"},'
SampleJSON := ' {"id": "ViewSource", "label": "View Source"},'
SampleJSON := ' {"id": "SaveAs", "label": "Save As"},'
SampleJSON := ' null,'
SampleJSON := ' {"id": "Help"},'
SampleJSON := ' {"id": "About", "label": "About Adobe CVG Viewer..."}'
SampleJSON := ' ],'
SampleJSON := ' "testbool": "true",'
SampleJSON := ' "testint": "1234567890",'
SampleJSON := ' "testreal": "1234567890.987654321"'
SampleJSON := '}}'
// Parse it, then grab the label of entity 12 within the items array
If SRP_JSON(ObjectHandle, "PARSE", SampleJSON) EQ "" then
LabelHandle = SRP_JSON(ObjectHandle, "GET", "menu.items[12].label")
SRP_JSON(ObjectHandle, "RELEASE")
end |
