Objective-C

Call a JavaScript Function Returning an Array

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Demonstrates how to call a JavaScript function that returns an array. Objective-C

#import <CkoStringBuilder.h>
#import <CkoJs.h>
#import <CkoJsonObject.h>

BOOL success = NO;

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

CkoStringBuilder *sbScript = [[CkoStringBuilder alloc] init];
success = [sbScript LoadFile: @"js_function_returning_array.js" charset: @"utf-8"];
if (success == NO) {
    NSLog(@"%@",sbScript.LastErrorText);
    return;
}

CkoJs *js = [[CkoJs alloc] init];

CkoJsonObject *result = [[CkoJsonObject alloc] init];
result.EmitCompact = NO;

//  Call Eval to add the function to the context's global object
success = [js Eval: sbScript result: result];
if (success == NO) {
    //  Examine the result for an exception.
    NSLog(@"%@",[result Emit]);

    //  Also examine the LastErrorText.
    NSLog(@"%@",js.LastErrorText);
    return;
}

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

CkoJsonObject *funcCall = [[CkoJsonObject alloc] init];

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

[funcCall UpdateString: @"name" value: @"getDays"];

success = [js CallFunction: funcCall result: result];
if (success == NO) {
    //  Examine the result for an exception.
    NSLog(@"%@",[result Emit]);

    //  Also examine the LastErrorText.
    NSLog(@"%@",js.LastErrorText);
    return;
}

NSLog(@"%@",[result Emit]);

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

//  Access each array value..
int count = [[result SizeOfArray: @"value"] intValue];
int i = 0;
while (i < count) {
    result.I = [NSNumber numberWithInt: i];
    NSLog(@"%@",[result StringOf: @"value[i]"]);
    i = i + 1;
}

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

[funcCall Clear];
[funcCall UpdateString: @"name" value: @"getRange"];
[funcCall UpdateInt: @"args[0]" value: [NSNumber numberWithInt: 14]];
[funcCall UpdateInt: @"args[1]" value: [NSNumber numberWithInt: 21]];
success = [js CallFunction: funcCall result: result];
NSLog(@"%@",[result Emit]);

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

count = [[result SizeOfArray: @"value"] intValue];
i = 0;
while (i < count) {
    result.I = [NSNumber numberWithInt: i];
    NSLog(@"%d",[[result IntOf: @"value[i]"] intValue]);
    i = i + 1;
}

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

[funcCall Clear];
[funcCall UpdateString: @"name" value: @"getEmployees"];
success = [js CallFunction: funcCall result: result];
NSLog(@"%@",[result Emit]);

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

count = [[result SizeOfArray: @"value"] intValue];
i = 0;
while (i < count) {
    result.I = [NSNumber numberWithInt: i];
    NSLog(@"%@%@",@"name: ",[result StringOf: @"value[i].name"]);
    NSLog(@"%@%@",@"role: ",[result StringOf: @"value[i].role"]);
    NSLog(@"%@%d",@"id: ",[[result IntOf: @"value[i].id"] intValue]);
    NSLog(@"%@",@"");
    i = i + 1;
}