Unicode C

Call a JavaScript Function Returning an Object

See more JavaScript Examples

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

#include <C_CkStringBuilderW.h>
#include <C_CkJsW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilderW sbScript;
    HCkJsW js;
    HCkJsonObjectW result;
    HCkJsonObjectW funcCall;

    success = FALSE;

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

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

    sbScript = CkStringBuilderW_Create();
    CkStringBuilderW_Append(sbScript,L"function getSettings() {");
    CkStringBuilderW_Append(sbScript,L"    return {");
    CkStringBuilderW_Append(sbScript,L"        theme: \"dark\",");
    CkStringBuilderW_Append(sbScript,L"        notifications: true,");
    CkStringBuilderW_Append(sbScript,L"        version: 1.0");
    CkStringBuilderW_Append(sbScript,L"    };");
    CkStringBuilderW_Append(sbScript,L"}");

    js = CkJsW_Create();

    result = CkJsonObjectW_Create();
    CkJsonObjectW_putEmitCompact(result,FALSE);

    //  Call Eval to add the function to the context's global object
    success = CkJsW_Eval(js,sbScript,result);
    if (success == FALSE) {
        //  Examine the result for an exception.
        wprintf(L"%s\n",CkJsonObjectW_emit(result));

        //  Also examine the LastErrorText.
        wprintf(L"%s\n",CkJsW_lastErrorText(js));
        CkStringBuilderW_Dispose(sbScript);
        CkJsW_Dispose(js);
        CkJsonObjectW_Dispose(result);
        return;
    }

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

    funcCall = CkJsonObjectW_Create();

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

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

    CkJsonObjectW_UpdateString(funcCall,L"name",L"getSettings");

    success = CkJsW_CallFunction(js,funcCall,result);
    if (success == FALSE) {
        //  Examine the result for an exception.
        wprintf(L"%s\n",CkJsonObjectW_emit(result));

        //  Also examine the LastErrorText.
        wprintf(L"%s\n",CkJsW_lastErrorText(js));
        CkStringBuilderW_Dispose(sbScript);
        CkJsW_Dispose(js);
        CkJsonObjectW_Dispose(result);
        CkJsonObjectW_Dispose(funcCall);
        return;
    }

    wprintf(L"%s\n",CkJsonObjectW_emit(result));

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

    //  Examine the object's members
    wprintf(L"theme: %s\n",CkJsonObjectW_stringOf(result,L"value.theme"));
    wprintf(L"notifications: %d\n",CkJsonObjectW_BoolOf(result,L"value.notifications"));
    wprintf(L"version: %d\n",CkJsonObjectW_IntOf(result,L"value.version"));

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


    CkStringBuilderW_Dispose(sbScript);
    CkJsW_Dispose(js);
    CkJsonObjectW_Dispose(result);
    CkJsonObjectW_Dispose(funcCall);

    }