Google Web应用程序将单元素数组视为单个字符数组

Question

I am building a web app with Google Apps Script. It currently consists of an HTML form that passes the form data to a GAS function that retrieves certain information from a Google spreadsheet, depending on the form data. It then returns that spreadsheet data to the HTML side and prints out a list.

Part of the HTML form is a set of checkboxes that looks like this:

<input type="checkbox" name="stage" value="startup" id="startup" />
<label for="startup">Startup</label><br>
<input type="checkbox" name="stage" value="yrs210" id="yrs210" />
<label for="yrs210">Years 2-10</label><br>
<input type="checkbox" name="stage" value="experienced" id="experienced" />
<label for="experienced">Experienced</label><br>
etc...

The checkbox values are compared to the contents of a certain column in the spreadsheet and used to determine what data to return.

To make a long story short (too late) , it works as expected when multiple checkboxes are checked. When only one is checked, however, it is treated not as a single element in an array but as an array made up of each of the characters. For example, "startup" becomes ["s","t","a","r","t","u","p"] . Then my script searches for each of those letters in the spreadsheet, and of course there are a lot of matches.

This is probably something really basic that I missed in trying to teach myself JavaScript. Any pointers? Ideas why this is happening?

In case it helps, here is the main part of my script:

var stage = formObject.stage;
//get spreadsheet contents
var ss = SpreadsheetApp.openById('ID');
var dataSheet = ss.getSheetByName('sheet1');
var dataRange = dataSheet.getDataRange();
var data = dataRange.getValues();
var cStage = 2; //Number of column containing stages
var cOutput = 4; //Number of column containing output

//compare selections to spreadsheet, list matches
var array1 = [];
for(var i = 0; i < stage.length; i++) {
  for(var j = 0; j < data.length; j++) {
    if(data[j][cStage - 1].indexOf(stage[i]) > -1) {
      array1.push(data[j][cOutput - 1]);
    }
  }
}
//loop to delete duplicate entries
var array = [];
for(var o = 0; o < array1.length; o++) {
  if(array.indexOf(array1[o]) == -1) {
    array.push(array1[o]);
  }
}
return array;

I assume this looks rather stupid, but I am using what I know, and it mostly works, except for this one issue. I am open to any and all advice, especially in regard to this one question about my single-element array being split up into an array of single-character elements.

Thanks!

Answer 1

When you select multiple checkboxes, the value is passed as an Array of strings as you are expecting. However, when you select only one checkbox, the value is passed as a String, rather than an Array.

Your code is then treating the string as an array, which leads to you looping over the individual characters.

You can use Array.isArray() to check if you are dealing with an Array or not, then adjust your code accordingly to handle the string.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray

You can use a line like the example below to place your plain string into an Array, avoiding the need to make significant modifications to your other code:

if(!Array.isArray(result)) result = [result];