Google Spreadsheet App Script error resolution: How to deal with “TypeError: Cannot read properties of undefined (reading ‘getSheetByName’)

While using App Script with Google Spreadsheets, you may encounter the error “TypeError: Cannot read properties of undefined (reading ‘getSheetByName’)”. This error indicates that when the script attempts to access a sheet in the spreadsheet, it is unable to retrieve the sheet correctly. This article details the cause of this error and how to resolve it.

Causes of the Error

The main causes of this error are

• The script is not correctly retrieving the active spreadsheet.
• The specified sheet name does not exist or is incorrect
• There is a problem with the script’s execution environment.

Solution

The easiest and most effective way to resolve this error is to reopen the App Script editor. The specific steps are as follows

1. Open a Google spreadsheet.
2. Select “Extensions” from the top menu.
3. Select “Apps Script” from the drop-down menu.
4. The App Script editor will open in a new tab.
5. Try running the script again.

This method often resolves errors. This is because reopening the App Script editor correctly initializes the script’s execution environment and properly sets up references to the active spreadsheet.

Technical Explanation

Here is a more detailed explanation of the technical background of this error:

• Spreadsheet reference: App Script normally retrieves the active spreadsheet using the SpreadsheetApp.getActiveSpreadsheet() method. However, if there is a problem with the script’s execution environment, this method may return undefined.
• Retrieving a sheet: After the spreadsheet reference has been successfully retrieved, the getSheetByName() method is used to access the specific sheet. If the spreadsheet reference is undefined, an attempt to call this method will result in a TypeError.
• Initializing the execution environment: Reopening the App Script editor will reinitialize the script’s execution environment and set the correct reference to the spreadsheet.

Other Solutions and Preventive Actions

In addition to reopening the editor, you can try the following

• Check the script: Make sure the sheet names are correct and spelled correctly.
• Error handling: Use try-catch blocks in your scripts to properly handle errors.
• Explicit Spreadsheet Retrieval: Another way to retrieve a spreadsheet explicitly is to use the spreadsheet’s ID.

function getSpecificSpreadsheet() {
  var spreadsheetId = 'your-spreadsheet-id-here';
  var spreadsheet = SpreadsheetApp.openById(spreadsheetId);
  var sheet = spreadsheet.getSheetByName('Sheet1');
  // subsequent processing
}

Using this method, a specific spreadsheet can be reliably retrieved and is less susceptible to environmental issues.

Conclusion

The “TypeError: Cannot read properties of undefined (reading ‘getSheetByName’)” error is primarily caused by problems with the script’s execution environment and the spreadsheet reference. While this can often be resolved by simply reopening the App Script editor, for more robust scripting, we recommend considering proper error handling and explicit methods of retrieving the spreadsheet. A combination of these methods will allow for more stable Google Spreadsheet automation.