Microsoft Certified Solutions Developer (MCSD) Certification Practice Test

What does the LastIndexOf method in the String class find?

1. Index of the first character

2. Length of the string

3. Index of the last occurrence of a character or substring

4. All occurrences of a character

The correct answer is: Index of the last occurrence of a character or substring

The LastIndexOf method in the String class is designed to locate the index of the last occurrence of a specified character or substring within the string. When this method is invoked, it scans the string from the end towards the beginning, which allows it to return the position of the last instance of the specified character or substring. This is particularly useful in scenarios where you need to identify how many times a certain character or substring appears in the string and in which position the last occurrence can be found. The method returns the zero-based index, starting from the beginning of the string, making it clear and straightforward for programmers to work with string manipulation tasks. This method can be key in various applications, such as parsing text, string comparisons, or validating content, as it provides more flexibility than simply finding the first occurrence.