Developers can often face the Cannot read property 'tolowercase' of undefined error when attempting to run JavaScript code. This error can be caused by a variety of different issues relative to coding, including syntax errors and failed functions. Fortunately, this error can often be solved with a few simple steps.
Step by Step Solution
- Check your syntax. It's possible that the error is being caused by a typo or syntax issue in your code. You can use the JSLint tool to help you detect potential syntax errors.
- Check for missing values. Make sure that any variables being called by your method are correctly being passed into the function. It's possible you are attempting to call a value that was never passed in, which can cause the
Cannot read property 'tolowercase' of undefinederror. - Check the inheritance of your values. Some values require the use of
thisto be referenced from the global scope. Make sure that the variables you are referencing can be found in the global scope. - Ensure that you are referencing the method correctly. Sometimes developers forget to prefix a method with its appropriate object name, which can cause the
Cannot read property 'tolowercase' of undefinederror.
FAQ
###Q: What could be causing this error?
A: This error is generally caused by some type of syntax issue, a missing value, incorrect inheritance of the value, or incorrect referencing of a method.
Q: How do I check for syntax errors?
A: You can use the JSLint tool to help you check for syntax errors in your code.
Q: What happens when I'm attempting to reference a variable that's never been passed in?
A: Attempting to access a variable that was never passed in can cause the Cannot read property 'tolowercase' of undefined error.
Q: Is it possible I'm referencing the wrong object?
A: Yes, the Cannot read property 'tolowercase' of undefined error can occur if you attempt to call the incorrect object. Make sure that it is properly referenced.
Q: Can I use other tools to find syntax errors?
A: Yes, there are a variety of different tools available like JSLint to help you find syntax and other coding errors. You can also use debugging tools as well as software testing to ensure your code is up to par.