C++

Call a JavaScript Function Returning an Object

See more JavaScript Examples

Demonstrates how to call a JavaScript function that returns an object. C++

#include <CkStringBuilder.h>
#include <CkJs.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    bool success = false;

    // This is the JavaScript function we'll call:

    // function getSettings() {
    //     return {
    //         theme: "dark",
    //         notifications: true,
    //         version: 1.0
    //     };
    // }

    CkStringBuilder sbScript;
    sbScript.Append("function getSettings() {");
    sbScript.Append("    return {");
    sbScript.Append("        theme: \"dark\",");
    sbScript.Append("        notifications: true,");
    sbScript.Append("        version: 1.0");
    sbScript.Append("    };");
    sbScript.Append("}");

    CkJs js;

    CkJsonObject result;
    result.put_EmitCompact(false);

    // Call Eval to add the function to the context's global object
    success = js.Eval(sbScript,result);
    if (success == false) {
        // Examine the result for an exception.
        std::cout << result.emit() << "\r\n";

        // Also examine the LastErrorText.
        std::cout << js.lastErrorText() << "\r\n";
        return;
    }

    // ------------------------------------------------------------------------------
    // Call the function getSettings()

    CkJsonObject funcCall;

    // Create JSON specifying the function name and arguments
    // The function has no arguments, so we only specify the name.

    // {
    //   "name": "getSettings",
    // }

    funcCall.UpdateString("name","getSettings");

    success = js.CallFunction(funcCall,result);
    if (success == false) {
        // Examine the result for an exception.
        std::cout << result.emit() << "\r\n";

        // Also examine the LastErrorText.
        std::cout << js.lastErrorText() << "\r\n";
        return;
    }

    std::cout << result.emit() << "\r\n";

    // Output:
    // {
    //   "type": "object",
    //   "value": {
    //     "theme": "dark",
    //     "notifications": true,
    //     "version": 1
    //   }
    // }

    // Examine the object's members
    std::cout << "theme: " << result.stringOf("value.theme") << "\r\n";
    std::cout << "notifications: " << result.BoolOf("value.notifications") << "\r\n";
    std::cout << "version: " << result.IntOf("value.version") << "\r\n";

    // Output:
    // theme: dark
    // notifications: True
    // version: 1
    }