小程序TypeError: eventChannel.on is not a function

这种错误通常是因为 `eventChannel` 对象没有正确初始化导致的。

在小程序中，`eventChannel` 是用于页面之间通信的一种方式。当你需要从一个页面向另一个页面传递数据时，可以使用 `eventChannel` 对象来实现。

在使用 `eventChannel` 对象前，需要先通过 `this.getOpenerEventChannel()` 方法获取到一个 `eventChannel` 对象。例如：

// 在 Page A 中
const eventChannel = this.getOpenerEventChannel()

// 在 Page B 中
const eventChannel = this.getEventChannel('eventChannelName')

如果在调用 `on` 方法时出现了 `TypeError: eventChannel.on is not a function` 的错误，可能是因为 `eventChannel` 对象并没有正确初始化。请确保在使用 `eventChannel` 对象之前，已经通过 `getOpenerEventChannel` 或 `getEventChannel` 方法获取到了一个有效的 `eventChannel` 对象。

相关问题

TypeError: stream.on is not a function

这个错误通常发生在尝试对一个非流对象调用 `.on()` 方法时。例如，如果你在一个普通的 JavaScript 对象上调用 `.on()` 方法，就会出现这个错误。

请检查你的代码，找到调用 `.on()` 方法的地方，并确保你正在调用它的对象是一个流对象。如果你不确定如何解决这个问题，请提供更多的上下文和代码，以便我可以帮助你解决问题。

data.reduce is not a function TypeError: data.includes is not a function

The error message you received suggests that `data` does not have a `reduce` or `includes` function.

Firstly, make sure that `data` is actually an array because both `reduce` and `includes` are array methods. You can check its type using `Array.isArray(data)`.

If `data` is indeed an array, then the error might be occurring because you are trying to call these methods on an undefined or non-array value within the array. In such cases, you should check if the specific element you are trying to call `reduce` or `includes` on exists and is of the expected type.

For example, you could use `Array.prototype.filter` to remove any undefined or non-array elements from `data` before using `reduce` or `includes` on it:

const validData = data.filter(element => Array.isArray(element));

Then, you can apply the desired methods on the filtered `validData` array. Remember to handle the case when `validData` is empty or doesn't contain the expected values.

If the issue persists, please provide more context or code snippets so that I can better understand the problem and assist you further.