How to modify the code to achieve a part of a matching IP address from left to right?

Teacher George's code could have achieved left-to-right matching of IP addresses, which is very practical in scenarios such as IP address filtering or access control, such as matching prefixes such as "11.9." However, the modified code can only be matched exactly. This article will explain how to modify the code to restore partial matching functions and be compatible with two database IP address formats:

1. 99.88, 110.52, 43.80.235, 11.9.67.180
2. "99.88", "110.52", "43.80.235", "11.9.67.180"

The problem is that the modified code loses partial matching logic. To solve this problem, we need to redesign the matching algorithm. The provided code snippet is too short to be modified directly. We need a complete code example to make specific modifications.

However, we can provide an improved algorithm idea:

Ideas for improving algorithms:

Assume that the IP address fragment that needs to be matchIP is matchIP and the database IP address list is dbiplist .

1. Preprocessing: Split the dbiplist string into an array of IP addresses according to commas. Also, remove double quotes (if any) at both ends of each IP address.

2. Partial Match: Iterate through each IP address dbIP in the IP address array. Check whether dbIP starts with matchIP . It can be implemented using the InStr(dbIP, matchIP) function. If InStr(dbIP, matchIP) = 1 , the match is successful.

3. Output result: If a matching IP address is found, output "ok"; otherwise, no content is output.

Sample code (VBScript):

This code demonstrates how to preprocess and partially match. You need to adjust it according to your actual code and database structure. The key is to use the InStr function for partial matching, and the correctness of the preprocessing steps to ensure that the code can handle two different database formats. Remember, this is just an example, you need to modify and improve it according to your actual environment.

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