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    <p>JSON is very simple and easy to figure out, once you understand the basic concepts. Have a look at <a href="http://json.org">http://json.org</a>, where it explains things.</p> <p>There are 4 basic concepts in JSON:</p> <p>A <em>value</em> is any JSON element: a basic string or number, an array, or an object. (Anything but a <em>pair</em>.)</p> <p>An <em>array</em> should be a familiar concept: an ordered list of values. The main difference from Delphi arrays is that JSON arrays don't have a defined type for the elements; they're simply "an array of JSON values."</p> <p>A <em>pair</em> is a key-value pair. The key can be a string or a number, and the value can be any JSON value.</p> <p>An <em>object</em> is an associative map of JSON pairs. You can think of it conceptually as a <code>TDictionary&lt;string, JSON value&gt;</code>.</p> <p>So if I wanted to take a JSON array of data like that, and put it in a TListBox, I'd do something like this (DBXJSON example, warning: not tested):</p> <pre><code>procedure TMyForm.LoadListBox(response: TJSONObject); var i: integer; ips: TJSONArray; ip: TJSONObject; pair: TJSONPair; begin ListBox.Clear; pair := response.Get('ips'); if pair = nil then Exit; ips := pair.value as TJSONArray; for i := 0 to ips.size - 1 do begin ip := ips.Get(i) as TJSONObject; pair := ip.Get('ip'); if pair = nil then ListBox.AddItem('???', ip.Clone) else ListBox.AddItem(pair.JsonString, ip.Clone); end; end; </code></pre> <p>Then you have a list of IP addresses, and associated objects containing the full record that you can get at if the user selects one. (If you wanted to put the entire contents of each record into the list control, have a look at <code>TListView</code>. It works better than <code>TListBox</code> for that.)</p> <p>And if you want to build an array of strings containing all the values, do something like this:</p> <pre><code>function JsonObjToStringArray(obj: TJsonObject): TArray&lt;string&gt;; var i: integer; begin SetLength(result, obj.Size); for i := 0 to obj.Size - 1 do result[i] := obj.Get(i).JsonValue.ToString; end; </code></pre> <p>This is all just sample code, of course, but it should give you something to build on.</p>
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    1. USMason Wheeler
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    1. COMany thanks Mason! The answer is great and i now understand the concepts. I'm a little confused, though i perhaps didn't explain myself in the original question enough (i did say it in the opener, but it's easy to forget those by the end of the question). I should mention that i've got the plaintext JSON (i.e. an unparsed string as retrieved via the API) in a `TMemo` and as such can't figure out how to place the `lines.text` of this into the `JSONObject` response required by the procedure. Also, `ips := pair.value as TJSONArray` returns `E2015 - Operator not applicable`.
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      1. USScott Pritchard
    2. CO@scott: Take a look at `TJSONObject.Parse`. And that line should probably use `pair.JsonValue` instead. My bad.
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      1. USMason Wheeler
 

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