How to solve javascript errors

Common types and solutions include: Syntax errors: Go through your code carefully, looking for typos, missing punctuation, or incorrect syntax structures. Reference errors: Check that the variable or function has been declared and make sure it is spelled correctly. Type error: Check the type of the variable and use the type conversion function to perform type conversion (if necessary). Range Error: Make sure the arguments passed to the function are within the allowed range. URI errors: Check that the parameters passed to URI handler functions are valid URI components and use the correct encoding and decoding functions.

#How to resolve JavaScript errors depends on the type of error and the circumstances. The following are some common JavaScript error types and their solutions:

1. SyntaxError:
   This type of error is usually due to typos and missing punctuation in the code. (such as semicolons, parentheses, etc.) or using incorrect grammatical structures.

   Solution:

   • Check the code carefully to find and correct typos.
   • Make sure all statements end with a semicolon (although semicolons are sometimes optional in modern JavaScript, adding them can improve code readability and avoid potential errors).
   • Make sure all brackets (parentheses, curly braces, square brackets) are paired and closed correctly.

2. ReferenceError:
   This type of error is usually caused by trying to access a reference to an undeclared variable or function.

   Solution:

   • Check whether the variable or function has been declared.
   • Check for spelling errors and make sure the name of the variable or function matches the name in the code that references it.
   • If you use a variable in a function, make sure the variable has been declared within the scope of the function.

3. TypeError (TypeError):
   This type of error is usually caused by trying to perform an unsupported operation on a value, or treating a value as the wrong type caused by the value of .

   Solution:

   • Check the type of the variable to make sure it is the type you expect.
   • Use the typeof operator to check the type of a variable.
   • If necessary, use type conversion functions (such as Number(), String(), parseInt(), parseFloat(), etc.) to convert the type of the variable.

4. RangeError:
   This type of error is usually caused by the value passed to the function exceeding the range that it can handle.

   Solution:

   • Check the parameters passed to the function to ensure that they do not exceed the range that the function can handle.
   • For numerical values, check whether there is overflow or underflow.

5. URI Error (URIError):
   This type of error is related to the global URI processing function, such as encodeURI() or decodeURI().

   Solution:

   • Check the parameters passed to the URI handler function to ensure that they are valid URI components.
   • Use the correct URI encoding and decoding functions.

6. Execution Error (ExecutionError):
   This type of error includes EvalError (rarely used because the use of the eval() function is usually unsafe) and InternalError ( An internal browser error that usually cannot be fixed by the developer).

   Solution:

   • Try to avoid using the eval() function because it may bring security risks and make debugging difficult.
   • For InternalError, this is usually a problem with the browser and may require updating the browser or reporting it to the browser developer.

In addition to the specific error types mentioned above, there are also some general methods for solving JavaScript errors:

• Use console debugging: Open the browser's developer tools and view the error information in the console. The console usually provides a detailed error description and the location of the error, which helps to quickly locate the problem.
• Step-by-step debugging: Set breakpoints in the developer tools, then execute the code step by step, observing the values ​​of variables and the execution flow of the program. This helps identify logic errors or execution flow problems.
• Simplify the problem: If the code is complex and difficult to debug, try simplifying the problem. Create a minimal example that only contains the problematic code, making it easier to locate the problem.
• Check the documentation and community: Check the relevant JavaScript documentation and community forums to see if anyone else has encountered similar problems and found solutions.
• Use code review tools: Using code review tools like ESLint can help uncover potential errors and irregular coding styles.

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