describe
After we wrote a lot of tags but nothing actually appeared, this error message appeared when we checked the console.
Solutions
Rendering error: "TypeError: Cannot read property of undefined (read 'toString')"
Global search friend toSrtring has no variable toString, but there is a variable carrying a toString(), so the affected variables can be removed by removing the toString() method.
analyze
We often receive some data through the API, but we often do the following things under an ideal situation. What if the returned object does not exist? What if a property in the returned object does not exist, so we must avoid using methods. For a variable, you must first determine whether the variable exists, and then modify the method.