JSON Editor¶

The JSON Editor provides a powerful environment for editing, validating, and querying JSON files with support for multiple JSON formats.

Version: 2.0.1

Note: The standalone JSON Editor tab has been retired. JSON editing — text editing plus the tree view and validation — now lives in the Unified Shell: open a .json file and the JSON editor view (text/tree) is available there. The capabilities below are unchanged; they are now part of the shell rather than a dedicated sidebar tab.

Overview¶

FreeXmlToolkit includes a full-featured JSON Editor that supports: - Standard JSON - RFC 8259 compliant - JSONC - JSON with Comments (single-line // and block /* */) - JSON5 - Extended JSON with trailing commas, unquoted keys, and comments

JSON in the Unified Shell JSON editing (text + tree view) in the Unified Shell

Features¶

Text Editor¶

Feature	Description
Syntax Highlighting	Color-coded JSON for easy reading
Auto Format	Beautify JSON with proper indentation
Minify	Compress JSON by removing whitespace
Undo/Redo	Full undo/redo support
Line Numbers	Numbered lines for easy navigation
Drag & Drop	Drop JSON files directly into the editor

Tree View¶

The tree view provides a hierarchical view of your JSON structure:

Feature	Description
Interactive Navigation	Click on nodes to jump to that location in the text
Expand/Collapse	Expand or collapse nodes to focus on specific areas
Search	Search for keys or values within the tree
Sync with Editor	Synchronize selection between tree and text
Type Icons	Visual icons for objects, arrays, strings, numbers, booleans, and null

Hover Information¶

When you hover over any element in the JSON editor, you'll see: - JSONPath - The full path to the current element (e.g., $.store.book[0].title) - Type - The JSON type (object, array, string, number, boolean, null) - Key - The property key name - Value - A preview of the value (truncated for long values)

JSONPath Queries¶

Execute JSONPath queries to extract data from your JSON documents:

Query Example	Description
`$.store.book[*].author`	All authors in the store
`$..author`	All authors anywhere in the document
`$.store.book[?(@.price < 10)]`	Books cheaper than 10
`$.store.book[0,1]`	First two books
`$.store.book[-1:]`	Last book

To run a query: 1. Open the Query Console (terminal icon in the toolbar, or Ctrl+Shift+X) - with a JSON document active it evaluates JSONPath 2. Enter your JSONPath expression 3. Run it to see the results in the console's result pane

Validation¶

Syntax Validation¶

Click Validate to check if your JSON is syntactically correct. The editor will report: - Parse errors with line and column numbers - Detected format (JSON, JSONC, or JSON5)

JSON Schema Validation¶

JSON documents bind a JSON Schema the same way XML documents bind an XSD:

Automatic: a top-level "$schema" member pointing at a schema file or URL (e.g. "$schema": "./product-schema.json") is detected when the file opens. Relative paths resolve against the document's folder; http(s) URLs are downloaded and cached. (Values pointing at json-schema.org meta-schemas are dialect declarations, not bindings, and are ignored.)
Manual: click the JSON Schema indicator in the status bar, use the JSON Schema source row in the Validation panel (Change link, favorites star, or drag & drop a .json schema onto the row or the status bar).

Validation runs via Run Validation in the panel, the toolbar's Validate button / F8, or continuously while typing (Validate while typing, on by default). Schema violations appear in the PROBLEMS list with the offending line number — clicking a problem jumps to it. Each problem also carries the failing schema keyword and the JSON pointer of the invalid value.

The validator supports JSON Schema Draft-07, 2019-09, and 2020-12; the dialect is selected by the schema's own $schema declaration (2020-12 is the default for schemas without one). Relative $refs between schema files resolve as expected.

Ready-made examples

The examples/json/ folder shipped with the application contains a complete demo set: a product-catalog schema with a relative $ref, a valid and a deliberately invalid instance (six line-navigable violations), and one dialect demo each for Draft-07 and 2019-09. Open examples/json/products-invalid.json and press F8 to see it in action.

Keyboard Shortcuts¶

Shortcut	Action
`Ctrl+N`	New JSON file
`Ctrl+O`	Open file
`Ctrl+S`	Save file
`Ctrl+Shift+S`	Save as
`Ctrl+Alt+F`	Format JSON
`F8`	Validate JSON
`Ctrl+Z`	Undo
`Ctrl+Y`	Redo
`Ctrl++`	Zoom in
`Ctrl+-`	Zoom out
`Ctrl+0`	Reset zoom

Supported Formats¶

JSON (Standard)¶

{
  "name": "John",
  "age": 30,
  "active": true
}

JSONC (JSON with Comments)¶

{
  // This is a single-line comment
  "name": "John",
  /* This is a
     multi-line comment */
  "age": 30
}

JSON5¶

{
  // Unquoted keys
  name: 'John',
  // Single quotes
  city: 'New York',
  // Trailing commas allowed
  items: [1, 2, 3,],
}

JSON files use the shell's single-row editor toolbar. Related actions sit in split buttons with a visible ▾ arrow menu; see Unified Shell - Toolbar for the full reference.

With a JSON file active, the relevant actions are:

Button	Description
New	Open the guided New File dialog (includes JSON)
Open	Open an existing file
Save ▾	Save the current document; the arrow menu holds Save As… and Save All
Undo / Redo	Undo or redo changes (icon buttons)
Format ▾	Pretty-print the JSON; the arrow menu holds Minify (compress by removing whitespace)
Query Console	Toggle the bottom query console - for JSON documents it runs JSONPath queries (icon button, Ctrl+Shift+X)
Validate	Check the JSON syntax (F8)

Actions that do not apply to JSON (e.g. Run or the XSLT transform) are greyed out. The Tree view is switched with the Text/Tree view switch at the right end of the toolbar.

Tree View Icons¶

Icon	Type
`{ }`	Object (blue)
`[ ]`	Array (green)
`" "`	String (gray)
`#`	Number (orange)
Toggle	Boolean (cyan)
`-`	Null (gray, italic)
`//`	Comment (green, italic)

Tips and Best Practices¶

Use the Tree View for navigating large JSON documents
Enable Auto-Format after pasting JSON from external sources
Use JSONPath to quickly extract specific data
Validate against Schema to ensure data quality
Drag and Drop files for quick access

XML Editor - Edit XML files with similar features
XSLT Developer - Transform JSON to other formats

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