TypeError: Cannot read property 'onError' of undefined

TypeError: Cannot read property 'onError' of undefined是JavaScript中常见的错误类型之一。它表示在尝试访问一个未定义或null的对象的属性时发生了错误。

这个错误通常发生在以下情况下：
1. 对象未被正确初始化或赋值。
2. 对象的属性名拼写错误或不存在。
3. 对象的属性值为undefined或null。

要解决个错误，你可以按照以下步骤进行排查：
1. 确保你正在访问的对象已经被正确初始化或赋值。
2. 检查你正在访问的属性名是否正确，确保没有拼写错误。
3. 确保对象的属性值不为undefined或null。

如果你能提供更多的上下文信息，比如代码片段或错误堆栈信息，我可以给出更具体的帮助。

相关问题

TypeError: Cannot read property 'on' of undefined

This error message indicates that there is an attempt to access the 'on' property of an undefined object. The 'on' property is typically used for event listeners in JavaScript.

To fix this error, you should first identify the object that is undefined and ensure that it is properly defined before attempting to access its properties. This may involve checking variable assignments, function returns, or object creation.

Here are some possible causes of this error:

1. The object being referenced has not been properly initialized or instantiated.
2. The object being referenced has been deleted or removed from memory.
3. The object being referenced is not of the expected type.
4. There is a typo or other syntax error in the code that is causing the object to be undefined.

To troubleshoot the issue, you can use the console.log() method to output the value of the object at various points in your code to identify where the error is occurring. Additionally, check the documentation for the APIs or libraries you are using to ensure that you are using the correct syntax and methods.

Error in v-on handler: "TypeError: Cannot read property 'fileListInfos' of undefined"

这个错误提示表明在处理一个事件时出现了问题。具体来说，代码中尝试读取一个未定义的属性 'fileListInfos' 导致了 TypeError。

要解决这个问题，你需要检查代码中涉及到该属性的部分。首先，确保该属性被正确定义和初始化。如果该属性是在数据对象中声明的，请确保它已经被正确初始化为一个合适的值。

另外，还要确保在使用该属性之前，该属性所属的对象已经被正确创建和赋值。如果你使用了某个函数或方法来处理事件，那么请检查该函数内部是否正确地访问了属性。

最后，如果你使用了某个外部库或组件，可能需要确认其是否被正确引入和初始化。

通过仔细检查代码并根据具体情况进行相应的修正，应该能够解决这个错误。