peError: Cannot read properties of undefined (reading 'catch')
时间: 2023-10-14 19:24:23 浏览: 193
jstree报错 Cannot read property ‘state’ of undefined
This error occurs when you are trying to access the property 'catch' on an undefined value. In JavaScript, when you try to access a property of an undefined value, it will throw an error.
To fix this error, you need to make sure that the value you are trying to access is defined before accessing its property. You can use the typeof operator to check if the value is undefined before accessing its property. Here is an example code:
```
let myValue; // undefined value
if(typeof myValue !== 'undefined') {
myValue.catch(error => {
console.log(error);
});
}
```
In this example, we first check if the value 'myValue' is defined before accessing its 'catch' property. If it is undefined, the code inside the if statement will not be executed, and the error will be avoided.
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