Uncover the Power of LastIndexOf() in C#
When working with strings in C#, having the right tools at your disposal can make all the difference. One such tool is the LastIndexOf() method, which allows you to pinpoint the last occurrence of a specific character or string within a given string.
* Syntax and Parameters: A Breakdown*
The syntax of the string LastIndexOf() method is straightforward: LastIndexOf(value, startIndex, count, comparisonType)
. Here, value
represents the substring you’re searching for, startIndex
marks the beginning of the search, count
specifies the number of character positions to examine, and comparisonType
determines the rules for the search.
What to Expect: Return Values Explained
So, what can you expect from the LastIndexOf() method? It returns the index of the last occurrence of the specified character or string. If the specified character or string is not found, it returns -1.
Real-World Examples: Putting LastIndexOf() to the Test
Let’s take a closer look at how LastIndexOf() works in practice.
Example 1: Searching with a Start Index
In this example, we’re searching for the character ‘c’ starting from index 2 towards the beginning of the string str
. The output reveals the index position of the last occurrence of ‘c’.
Example 2: Searching with a Start Index and Count
Here, we’re searching for the characters ‘e’ and ‘r’ starting from index 5 towards the beginning of the string str
, examining only 2 character positions. The output shows the index position of the last occurrence of either ‘e’ or ‘r’.
Example 3: Searching with StringComparison
In this example, we’re demonstrating the use of StringComparison
enumeration values to specify the rules for the search. We’re ignoring letter case in the first search and considering letter case in the second search. The output highlights the difference in results based on the comparison type used.
By mastering the LastIndexOf() method, you’ll be able to tackle complex string manipulation tasks with ease and precision.