Delphi ActiveX

Call a JavaScript Function Returning an Array

See more JavaScript Examples

Demonstrates how to call a JavaScript function that returns an array. Delphi ActiveX

var
success: Integer;
sbScript: TChilkatStringBuilder;
js: TChilkatJs;
result: TChilkatJsonObject;
funcCall: TChilkatJsonObject;
count: Integer;
i: Integer;

begin
success := 0;

//  ----------------------------------------------------------------------------------
//  The Javascript functions called in this example are shown at the bottom of this page.
//  -----------------------------------------------------------------------------------

sbScript := TChilkatStringBuilder.Create(Self);
success := sbScript.LoadFile('js_function_returning_array.js','utf-8');
if (success = 0) then
  begin
    Memo1.Lines.Add(sbScript.LastErrorText);
    Exit;
  end;

js := TChilkatJs.Create(Self);

result := TChilkatJsonObject.Create(Self);
result.EmitCompact := 0;

//  Call Eval to add the function to the context's global object
success := js.Eval(sbScript.ControlInterface,result.ControlInterface);
if (success = 0) then
  begin
    //  Examine the result for an exception.
    Memo1.Lines.Add(result.Emit());

    //  Also examine the LastErrorText.
    Memo1.Lines.Add(js.LastErrorText);
    Exit;
  end;

//  ------------------------------------------------------------------------------
//  Call each function

funcCall := TChilkatJsonObject.Create(Self);

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

funcCall.UpdateString('name','getDays');

success := js.CallFunction(funcCall.ControlInterface,result.ControlInterface);
if (success = 0) then
  begin
    //  Examine the result for an exception.
    Memo1.Lines.Add(result.Emit());

    //  Also examine the LastErrorText.
    Memo1.Lines.Add(js.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add(result.Emit());

//  Output:
//  {
//    "type": "array",
//    "value": [
//      "Monday",
//      "Tuesday",
//      "Wednesday",
//      "Thursday",
//      "Friday"
//    ]
//  }

//  Access each array value..
count := result.SizeOfArray('value');
i := 0;
while i < count do
  begin
    result.I := i;
    Memo1.Lines.Add(result.StringOf('value[i]'));
    i := i + 1;
  end;

//  ------------------------------------------------------------------------------
//  Call the getRange(start,end) function

funcCall.Clear();
funcCall.UpdateString('name','getRange');
funcCall.UpdateInt('args[0]',14);
funcCall.UpdateInt('args[1]',21);
success := js.CallFunction(funcCall.ControlInterface,result.ControlInterface);
Memo1.Lines.Add(result.Emit());

//  Output:
//  {
//    "type": "array",
//    "value": [
//      14,
//      15,
//      16,
//      17,
//      18,
//      19,
//      20,
//      21
//    ]
//  }

count := result.SizeOfArray('value');
i := 0;
while i < count do
  begin
    result.I := i;
    Memo1.Lines.Add(IntToStr(result.IntOf('value[i]')));
    i := i + 1;
  end;

//  ------------------------------------------------------------------------------
//  Call the getEmployees() function

funcCall.Clear();
funcCall.UpdateString('name','getEmployees');
success := js.CallFunction(funcCall.ControlInterface,result.ControlInterface);
Memo1.Lines.Add(result.Emit());

//  Output:
//  {
//    "type": "array",
//    "value": [
//      {
//        "id": 101,
//        "name": "Alice",
//        "role": "Dev"
//      },
//      {
//        "id": 102,
//        "name": "Bob",
//        "role": "Manager"
//      }
//    ]
//  }

count := result.SizeOfArray('value');
i := 0;
while i < count do
  begin
    result.I := i;
    Memo1.Lines.Add('name: ' + result.StringOf('value[i].name'));
    Memo1.Lines.Add('role: ' + result.StringOf('value[i].role'));
    Memo1.Lines.Add('id: ' + IntToStr(result.IntOf('value[i].id')));
    Memo1.Lines.Add('');
    i := i + 1;
  end;

JavaScript

function getDays() {
    return ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday"];
}

function getRange(start, end) {
    var arr = [];
    for (var i = start; i <= end; i++) {
        arr.push(i);
    }
    return arr;
}
// Usage: getRange(1, 5) -> [1, 2, 3, 4, 5]

function getEmployees() {
    return [
        { id: 101, name: "Alice", role: "Dev" },
        { id: 102, name: "Bob", role: "Manager" }
    ];
}