Google Apps脚本Web应用程序中的异常处理

Question

I want to write try catch error handling mechanism in google apps script. I've deployed a web app and i want that if by any means any part of the functions written in script failed to execute, i want to put custom message on browser screen.

Lets go with program... First method which will get executed

function doGet(e){
  //Calling method
  methodCall();
  return HtmlService.createHtmlOutputFromFile('success');
}

Now lets say, inside method call there is some line which is error prone which will cause error if supply with improper inputs. So how could i capture this error and displaying custom error message on browser instead of success file's content.

function methodCall(){
   //Call to some Google API
  try{
    DriveApp.getFiles();
  }catch(err){
    return HtmlService.createHtmlOutput("<p>Custom error message</p>"); 
  } 
}

So by the end of loading the page, user can see the custom error message on his browser.

Answer 1

I'm not too familiar with Web Apps nor have I tested the code below but it should work or at least give you something to go on.

A couple of things.

1. Create a variable to store the value returned from the methodCall() function.

2. In the methodCall() function you cant return the HtmlService, instead if there is an error return the message that you want to output. If there is no error the return nothing.

3. In your doGet(e) check var response if nothing has been returned it will be false if anything has been returned it will be true then return your Html in the doGet.

4. In your code you have createHtmlOutputFromFile('success'); should this be createHtmlOutput('success') .

     function doGet(e){ //Calling method var response = methodCall(); if(response){ return HtmlService.createHtmlOutput(response); } else { return HtmlService.createHtmlOutputFromFile('success'); } function methodCall(){ //Call to some Google API try{ DriveApp.getFiles(); }catch(err){ return "<p>Custom error message</p>"; } return; }