jQuery toUpperCase/toLowerCase Example

JavaScript code snippets used to convert text to uppercase and lowercase. This is a simple example to demonstrate changes to form input values. See: jQuery titleCaps function

jQuery('form').submit(function() { jQuery('input#value').val(function(i, val) { return val.toUpperCase(); return val.toLowerCase(); }); });

FAQ (FAQ) of the jQuery toUpperCase() and toLowerCase() methods

What is the difference between jQuery toUpperCase() and toLowerCase() methods?

jQuery's toUpperCase() and toLowerCase() methods are used to change the case of text in JavaScript. The toUpperCase() method converts the string to uppercase letters, while the toLowerCase() method converts the string to lowercase letters. These methods do not change the original string, but return a new string with the required case.

How to use the toLowerCase() method in jQuery?

The method using toLowerCase() in jQuery is very simple. You just need to call the method on the string you want to convert to lowercase. Here is an example:

var str = "Hello World!"; var lowerCaseStr = str.toLowerCase(); console.log(lowerCaseStr); // Output: "hello world!"

In this example, the string "Hello World!" is converted to lowercase using the toLowerCase() method.

Can I use the toUpperCase() method for numbers or special characters?

jQuery's toUpperCase() method affects only alphabetical characters. Numbers, special characters, and spaces are not affected by this method. If you call toUpperCase() on a string that contains only numbers or special characters, the original string is returned without any changes.

Are the toUpperCase() and toLowerCase() methods case sensitive?

No, the toUpperCase() and toLowerCase() methods in jQuery are case-insensitive. They convert all alphabetical characters in the string to the desired case regardless of their original case.

Can I use the toUpperCase() and toLowerCase() methods with other jQuery methods?

Yes, you can link the toUpperCase() and toLowerCase() methods with other jQuery methods. This is a common practice in jQuery that can make your code more concise and easy to read.

How to convert only the first letter of a string to uppercase?

To convert only the first letter of the string to uppercase in jQuery, you can use the charAt() method and the toUpperCase() method. Here is an example:

var str = "hello world!"; var firstLetterUpperCaseStr = str.charAt(0).toUpperCase() str.slice(1); console.log(firstLetterUpperCaseStr); // Output: "Hello world!"

In this example, the first letter of the string "hello world!" is converted to uppercase.

What happens if I call the toLowerCase() method on an empty string?

If you call the toLowerCase() method on an empty string in jQuery, it will return another empty string. The toLowerCase() method does not change the original string, so calling it on an empty string will not produce any errors or unexpected results.

Can I use the toUpperCase() and toLowerCase() methods for non-string data types in jQuery?

jQuery's toUpperCase() and toLowerCase() methods are designed to handle strings. If you try to use these methods for non-string data types, you will receive a TypeError. To avoid this, always make sure that the data you are processing is a string before calling these methods.

Are the toUpperCase() and toLowerCase() methods in jQuery supported in all browsers?

Yes, the toUpperCase() and toLowerCase() methods are part of the JavaScript ECMAScript standard and are supported in all modern browsers, including Chrome, Firefox, Safari, and Edge.

How to convert a string to title case in jQuery?

To convert a string to title case in jQuery, you can use the toLowerCase() and toUpperCase() methods as well as the split() and join() methods. Here is an example:

var str = "hello world!"; var titleCaseStr = str.toLowerCase().split(' ').map(function(word) { return word.charAt(0).toUpperCase() word.slice(1); }).join(' '); console.log(titleCaseStr); // Output: "Hello World!"

In this example, the string "hello world!" is converted to title case, which means that the first letter of each word is capitalized.

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