Code errors are a common occurrence, and we need to determine what causes them and how to avoid them.
1. Uncaught TypeError: Cannot read property
This error indicates that there is no attribute, usually the attribute before the value is undefined or null.
TypeError: ‘undefined’ is not a function
This error is usually reported when executing a method on an object that does not exist. Indicates that the method does not exist in this object.
3. Uncaught RangeError: Maximum call stack
You get this error when you recurse and you don’t write boundary condition judgments, because the function keeps repeating itself.
TypeError: Cannot read property ‘length’ 4. TypeError: Cannot read property ‘length’
If the length attribute is null or undefined, this error will be reported.
5. Uncaught TypeError: Cannot set property
This error is reported if the property is preceded by null or undefined.
6. ReferenceError: event is not defined
In most cases, you use undefined without declaring the variable.
Conclusion: code error is mostly caused by null and undefined, so when writing code to take into account some special cases of processing, to avoid errors.