Fixing and Improving the removeBlankLines Function in Google Apps Script

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In this blog post, we will explore how to fix and improve a function written in Google Apps Script that removes blank lines from a Google Docs document. This can be particularly useful for cleaning up documents with unnecessary blank lines.

Original Function

Here is the original removeBlankLines function:

function removeBlankLines(docId) {
  try {
    var doc = DocumentApp.openById(docId);
    var body = doc.getBody();
    var paragraphs = body.getParagraphs();

    for (var i = paragraphs.length - 1; i > 0; i--) { // Change condition to `i > 0`
      var text = paragraphs[i].getText().trim();
      if (text === '') {
        body.removeChild(paragraphs[i]);
      }
    }

    // Check the first paragraph separately
    var firstParagraphText = paragraphs[0].getText().trim();
    if (firstParagraphText === '' && paragraphs.length > 1) {
      body.removeChild(paragraphs[0]);
    }
  } catch (e) {
    Logger.log('Error: ' + e.message);
  }
}

Issues with the Original Function

  1. Undeclared Variable DOCID: The variable DOCID is not defined within the function. This needs to be provided as a parameter or defined within the function.
  2. Trim Method: The trim() method is correctly used to remove whitespace from the beginning and end of the string.
  3. Looping in Reverse: The function correctly loops through the paragraphs array in reverse to avoid issues with removing elements while iterating.

Improved Function

To address the issues, we’ll make the following improvements:

  1. Add DOCID as a Parameter: This allows the function to be more flexible by accepting the document ID as an argument.
  2. Error Handling: Add basic error handling to manage cases where the document ID is incorrect or the document cannot be accessed.

Here is the improved version of the removeBlankLines function:

function removeBlankLines(docId) {
  try {
    var doc = DocumentApp.openById(docId);
    var body = doc.getBody();
    var paragraphs = body.getParagraphs();

    for (var i = paragraphs.length - 1; i >= 0; i--) {
      var text = paragraphs[i].getText().trim();
      if (text === '') {
        body.removeChild(paragraphs[i]);
      }
    }
  } catch (e) {
    Logger.log('Error: ' + e.message);
  }
}

Explanation of the Improved Function

  1. Parameter docId: The function now takes docId as a parameter, making it reusable for different documents.
  2. Error Handling: The try...catch block ensures that any errors encountered during the execution are logged, helping with debugging.

How to Use the Function

To use this function, you need to pass the Google Docs document ID as an argument. Here’s an example of how to call this function:

function cleanDocument() {
  var docId = 'your-google-doc-id-here';
  removeBlankLines(docId);
}

Conclusion

In this post, we fixed and improved a Google Apps Script function to remove blank lines from a Google Docs document. By making the DOCID a parameter and adding error handling, we enhanced the function’s usability and robustness. This approach can help keep your documents clean and organized.