JPath

💡 The JPath class gets or sets values of an object or array, without eval js func invoked. 
| 🗂 Library  |  | 🏷 ver. 2.0.5 |

| 🗓 Updated  | 🌷 Spring 2026 | 07. Mai AD 2026 07:23:20 UTC |

| 📐 Size     | 🗂 Folder: 105 KB | 📦 Tarball: 10 KB | 📄 .js: 14 KB |

| ⚡ JS Engine | 🌐 Browser: ✅ yes | 🧭 Express: ✅ yes | 🖥️ Console: ✅ yes |

Examples

JPath Expression 

let jpathExpression_js: string                   = "data.records[0].id";
let jpathExpression_points_joined: string        = "data.records.0.id";
let jpathExpression_jsonkey_ext_symbols: string  = "[data][records][0][field 2]";

In HTML 

<!-- 💡 In `.html` for the 'js framework like' Reactivity by central json data in a SPA. -->
<html>
  ...
  <div data-jpath="data.records.0.id"></div>
  ...

  <script src="node_modules/@jaisocx/jpath/transpiled/Simple/JPathData.js"></script>
        <script src="node_modules/@jaisocx/jpath/transpiled/Simple/JPath.js"></script>
        <script>
    // DOMContentLoaded ...
  </script>
</html>

Typescript 

let obj: any = {
  "data": {
    "records": [
      { "id": 1, "field 2": "text line of field 2" }
    ]
  }
};
let jPath: JPath = new JPath();
let jpathExpression: string = "data.records[0][field 2]";
let field2: any = jPath.getByJPathExpression( obj, jpathExpression );
console.log ( field2 );
// $ _ text line of field 2

Structure 

📚 JPath
    🗂 src/
      📄 index.ts
      📄 JPath.ts
      📄 JPathData.ts
      📄 JPathDataInterface.ts
      📄 JPathInterface.ts
    📊 test/
      📄 JPath_Test.js
      📄 Split_Test.js
    🗂 transpiled/
      🗂 CommonJS/
      🗂 ESNext/
      🗂 Simple/
        📄 JPath.js
        📄 JPathData.js
    📦 jaisocx-jpath-2.0.4.tgz
    📄 package.json
    📄 package-lock.json
    📒 README.md

Interfaces

JPathInterface 

// $ _ ${package}/src/JPathInterface.ts

// @class JPath. 💡 To lookup in js objects and arrays, without eval js func invoked.
export interface JPathInterface {

  // jpath string exression as "subtree[1].opened" => [ "subtree", 1, "opened" ]
  parse ( jpathExpression: string ): (string|number)[];

  // @invokedBy method parse(), splits with symbol point, adds to jpathArray, numeric array elem id or textual field name.
  parseDotted ( jpathExpressionDotted: string, jpathArray: ( string|number )[] ): number;

  serialize ( jpath: (string|number)[], delimiter: string, start: string, finish: string ): string;

  getByJPathExpression ( obj: any, jpathExpression: string ): any;

  // faster than JPath.getByJPathExpression( jpathExpression: string, value: any );
  getByJPath ( obj: any, jpath: (string|number)[] ): any;

  setByJPathExpression ( obj: any, jpathExpression: string, value: any ): JPathInterface;
  setByJPath ( obj: any, jpath: (string|number)[], value: any ): JPathInterface;

  setByJPathWalkFlatRebuild ( obj: any, jpath: (string|number)[], value: any, nameHolderId: string, nameId: string, branchName: string ): JPathInterface;
}

JPathDataInterface 

// $ _ ${package}/src/JPathDataInterface.ts

// @class JPathData. 💡 The data record for 2 fields: jpathExpression and jpathArray.
export interface JPathDataInterface {
  getJPathExpression(): string;
  getJPath(): ( string | number )[];

  setJPathExpression( jpathExpression: string ): JPathDataInterface;
  setJPath( jpath: ( string | number )[] ): JPathDataInterface;
}
Have a nice day, Jaisocx Software Architect Elias