javascript 在 Apps 脚本中，如何在自定义函数中包含可选参数
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In Apps Script, How to include optional arguments in custom functions
提问by Jarod Meng
I want to write a custom function which has some mandatory arguments but can also accept a few optional arguments. I couldn't find any documentation on this. Does anyone know? Is it similar to Javascript?
我想编写一个自定义函数，它有一些强制参数，但也可以接受一些可选参数。我找不到任何关于此的文档。有人知道吗？它类似于Javascript吗？
回答by Eric Koleda
Custom functions don't have a concept of required and optional fields, but you can emulate that behavior using logic like this:
自定义函数没有必填字段和可选字段的概念，但您可以使用如下逻辑模拟该行为：
function foo(arg1, opt_arg2) {
if (arg1 == null) {
throw 'arg1 required';
}
return 'foo';
}
It's convention to use the prefix "opt_" for optional parameters, but it's not required.
使用前缀“opt_”作为可选参数是惯例，但这不是必需的。
回答by Magne
Yes, it is JavaScript (with a limited support for JsDoc too), so you can have an optional parameter with a default value:
是的，它是 JavaScript（对 JsDoc 的支持也有限），所以你可以有一个带有默认值的可选参数：
/**
* This is myFunction.
* @param {number} arg1 - Some number.
* @param {string} arg2 - Some string.
* @param {number} arg3 - [OPTIONAL] Additional numbers or ranges to add to value1.
* @customFunction
**/
function myFunction(arg1, arg2, arg3=false) {
return arg3;
}
And then you could call it in your spreadsheet using either:
然后您可以使用以下任一方法在电子表格中调用它：
=myFunction(1, "somestring", true)
Or without the optional parameter:
或者没有可选参数：
=myFunction(1, "somestring")
Since JavaScript dynamically handles the parameter list.
由于 JavaScript 动态处理参数列表。
