Increment ID from last row google apps script

问题

I coded something for google apps script. It is to increment ID +1 based on the last row. Everything is working so far except for the numbering of the new ID, instead of appearing as a number.

The result appears as R-NaN instead of R-002 or something similar

What do you think should I revise in my code? Thank you.

function new_item() {

  // Get current spreadsheet
  var app = SpreadsheetApp;
  var ss = app.getActiveSpreadsheet();
  var mysheet = ss.getActiveSheet();

  // Set date to today in update field at the top of the sheet
  var now = new Date();
  mysheet.getRange(1,4).setValue(now);
  
  // Last non-empty row
  var rlast = mysheet.getLastRow();
  Logger.log("Last row = " + rlast);
  
  // Insert Row below
  mysheet.insertRows(rlast+1);
  var r = rlast+1;
  
  // Copy format from row above
  var sourcerange = mysheet.getRange(rlast + ":" + rlast);
  var targetrange = mysheet.getRange(r + ":" + r);
  sourcerange.copyTo(targetrange, {formatOnly:true});
  
  // Col. 2 : Risk identity
  var riskid = mysheet.getRange(rlast,2).getValue();
  if (riskid.length > 3){
    // Extract number ex. 3
    var riskidnb = riskid.substring(1,riskid.length);
    // Increase risk number +1
    riskidnb++
    // Convert to string "0004"
    var s = "000" + riskidnb
    // Write risk nb i.e. "R004"
    mysheet.getRange(r,2).setValue("R-"+ s.substring(s.length-4))
  }

``´

回答1:

Explanation / Issue:

Your code really depends on the value of the cell in column B last row:

  var riskid = mysheet.getRange(rlast,2).getValue();

There are two scenarios but I believe the second applies to your issue:

If the value in the cell is a number (e.g. 35233) then riskid will be an integer and therefore riskid.length will return null and as a result the if condition will evaluate to false. In this case, you can either use getDisplayValue or toString() instead to get the number as string and then you can apply .length to it:
```
var riskid = mysheet.getRange(rlast,2).getValue();
```
If the value in the cell is a string (e.g. R112) then the if condition will evaluate to true. If you do that:
```
var riskidnb = riskid.substring(1,riskid.length);
```
riskidnb will be 112 but this is still a string and therefore if you do riskidnb++ you will get NAN like the issue you have right now. In order to fix that, convert riskidnb to integer:
```
var riskidnb = parseInt(riskid.substring(1,riskid.length));
```
then you can do riskidnb++ and finally convert it back to string:
```
var s = "000" + riskidnb.toString();
```

Solution:

function new_item() {

  // Get current spreadsheet
  var app = SpreadsheetApp;
  var ss = app.getActiveSpreadsheet();
  var mysheet = ss.getActiveSheet();

  // Set date to today in update field at the top of the sheet
  var now = new Date();
  mysheet.getRange(1,4).setValue(now);
  
  // Last non-empty row
  var rlast = mysheet.getLastRow();
  Logger.log("Last row = " + rlast);
  
  // Insert Row below
  mysheet.insertRows(rlast+1);
  var r = rlast+1;
  
  // Copy format from row above
  var sourcerange = mysheet.getRange(rlast + ":" + rlast);
  var targetrange = mysheet.getRange(r + ":" + r);
  sourcerange.copyTo(targetrange, {formatOnly:true});
  
  // Col. 2 : Risk identity
  var riskid = mysheet.getRange(rlast,2).getValue();
  if (riskid.length > 3){
    // Extract number ex. 3
    var riskidnb = parseInt(riskid.substring(1,riskid.length));
    // Increase risk number +1
    riskidnb++
    // Convert to string "0004"
    var s = "000" + riskidnb.toString();
    // Write risk nb i.e. "R004"
    mysheet.getRange(r,2).setValue("R-"+ s.substring(s.length-4))
  }
}

Output:

来源：https://stackoverflow.com/questions/64680059/increment-id-from-last-row-google-apps-script

标签

javascript

google-apps-script

google-sheets