Understanding the type error in JavaScript when accessing properties of undefined

Hi ​@david rodriguez ,

You are exactly correct. But we need to see a screenshot of the input data to know why this is happening. Are you mapping the data correctly?

Hi ​@david rodriguez 

For us to have more info about the error, post screenshots showing how your Zap Code step is configured along with including the Code.

TIP: Try asking ChatGPT for help with your code.

3131415;25442011;25442640;6019602-2;V3.4.36;630 

THAT IS THE QR DATA OF THE QR

​@david rodriguez 

Can you provide the full JavaScript code?

// this is wrapped in an `async` function

// you can use await throughout the function

// reemplaza con la variable que Zapier te pase

let stringzap = inputData.codbar;

    let largo = stringzap.length;

    // rest of your code

    let posicion = stringzap.indexOf(';');

const clave_prodzap = stringzap.substring(0,posicion);

let posicion2 = stringzap.indexOf(';',posicion+1)

let inicialzap = stringzap.substring(posicion+1,posicion2);

let posicion3 = stringzap.indexof(';',posicion2+1);

let finalzap = stringzap.substring(posicion2+1,posicion3);

let posicion4 = stringzap.indexof(';',posicion3+1);

let posicion5 = stringzap.indexof(';',posicion4+1);

let posicion6 = stringzap.indexof(';',posicion5+1);

let posicion7 = stringzap.indexof(';',posicion6+1);

let cantzap = stringzap.substring(posicion6+1,posicion7);

let posicion8 = inicialzap.indexOf('H');

if (posicion8 = 0)  {

  ´let numero = inicialzap.substring(5,6);

  let prefijozap=inicialzap.substring(0,5);

  numero = inicialzap;

}

else

{

  let numero = inicialzap;

  prefijozap='';

}

let numeroEntero = parseInt(numero, 10);

for (i = 0; i <= cantzap; i++) {

  numeroentero = inicialzap + i;

  serialarray = serialarray + prefijozap + numeroentero.tostring.padStart(6, '0') + ';';

}

output {serialarray};

​@david rodriguez 
What happened to the screenshot of the Code step and input value?

​@david rodriguez 

Try this Code from ChatGPT:

let stringzap = inputData.codbar;

// Step 1: Parse QR code segments
let parts = stringzap.split(';');
let inicialzap = parts[1];
let cantzap = parseInt(parts[5], 10); // sixth item is the count

// Step 2: Get prefix/starting number
let prefijozap = '';
let numero = '';

if (inicialzap.startsWith('H')) {
  numero = inicialzap.substring(5, 6);
  prefijozap = inicialzap.substring(0, 5);
} else {
  numero = inicialzap;
}

let numeroEntero = parseInt(numero, 10);

// Step 3: Generate serials efficiently using an array
let serialArray = [];

for (let i = 0; i <= cantzap; i++) {
  let numeroActual = numeroEntero + i;
  let serial = prefijozap + numeroActual.toString().padStart(6, '0');
  serialArray.push(serial);
}

// Step 4: Return as semicolon-separated string OR array
return {
  serialarray: serialArray.join(';'), // or just return serialArray
  count: serialArray.length
};

all these with the code you sendme 

Failed to run your code

Your code had an error. See details below: Error: Sandbox.Timedout: RequestId: df63fbed-7322-4956-a414-9d84f5d051a1 Error: Task timed out after 10.00 seconds

What this error means:
The error "TypeError: Cannot read property 'length' of undefined" indicates that the JavaScript code is attempting to access the length property of a variable that is currently undefined. In this case, it likely means that the input data codbar is not being passed correctly from the previous step, resulting in the variable stringzap being undefined.

How to fix it:

1. Check Previous Step Output: Ensure that the previous step (BranchingAPI) is correctly outputting the expected value for Codigo_Barras. Verify that the output contains the expected data format.
2. Test Input Data: In the Code by Zapier step, test the input data to confirm that {{308132689__data__value__Codigo_Barras}} is returning a valid string. If it’s empty or undefined, the code will fail.
3. Add Error Handling: Modify the JavaScript code to include error handling that checks if inputData.codbar is defined before proceeding with the parsing logic. This can prevent the code from failing if the input is not as expected.
4. Review Zap Configuration: Ensure that the Zap is configured correctly and that all necessary fields are filled out in the previous steps to pass the required data to this step.

​@david rodriguez 

Did you try working with ChatGPT to fix your code?
Share screenshots of your config/errors and share you code so the AI has context.

If you need to hire help, there is a directory of Certified Zapier Experts: https://zapier.com/experts

YES I FIX MY CODE THANKS

HAVE ANOTHER ERROR 

BUT ALL AROUND THE SAME FACTOR

​@david rodriguez 

Best to continue to work with ChatGPT to get your code corrected.

​@david rodriguez 

Try the revised code above.

new code is this

// Get the QR code data string from inputData let stringzap = inputData.codbar; // Example: "3131415;25442011;25442640;6019602-2;V3.4.36;630" // Parse the first value: product key (before the first semicolon) let posicion = stringzap.indexOf(';'); let clave_prodzap = stringzap.substring(0, posicion); // Parse the second value: "inicialzap" (after first semicolon) let posicion2 = stringzap.indexOf(';', posicion + 1); let inicialzap = stringzap.substring(posicion + 1, posicion2); // Parse the third value: "finalzap" (after second semicolon) let posicion3 = stringzap.indexOf(';', posicion2 + 1); let finalzap = stringzap.substring(posicion2 + 1, posicion3); // Skip parsing 4th and 5th segments — they are not used here let posicion4 = stringzap.indexOf(';', posicion3 + 1); let posicion5 = stringzap.indexOf(';', posicion4 + 1); let posicion6 = stringzap.indexOf(';', posicion5 + 1); // Parse the 6th value: quantity of serials to generate let posicion7 = stringzap.length; let cantzap = stringzap.substring(posicion6 + 1, posicion7); // Initialize prefix and serial number variables let prefijozap = ''; let numero = ''; // Check if "inicialzap" starts with an "H" (special case) let posicion8 = inicialzap.indexOf('H'); if (posicion8 === 0) { // If it starts with H, treat the first 5 chars as a prefix and 6th char as the number numero = inicialzap.substring(5, 6); prefijozap = inicialzap.substring(0, 5); } else { // Otherwise, treat the full string as the number numero = inicialzap; prefijozap = ''; } // Convert extracted strings to integers for arithmetic let numeroEntero = parseInt(numero, 10); let cantidad = parseInt(cantzap, 10); // Initialize output string let serialarray = '';

yes 

same error

hi thanks the code i working

the output information is send in a array of objects

the question how i can have access to  this information from another function in zap 

can you help me?

​@david rodriguez 

Help link for how to map variables between Zap steps: https://help.zapier.com/hc/en-us/articles/8496343026701-Send-data-between-steps-by-mapping-fields

Storage options:

• Zapier Table: https://zapier.com/apps/zapier-tables/integrations#triggers-and-actions
• Storage: https://zapier.com/apps/storage/integrations#triggers-and-actions
• Airtable: https://zapier.com/apps/airtable/integrations#triggers-and-actions