Find and replace text in a string using C#

Posted by Joey Morani on Stack Overflow See other posts from Stack Overflow or by Joey Morani
Published on 2012-08-29T00:48:54Z Indexed on 2012/08/29 3:38 UTC
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c#

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string

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find-and-replace

Anyone know how I would find & replace text in a string? Basically I have two strings:

string firstS = "/9j/4AAQSkZJRgABAQEAYABgAAD/2wBDABQODxIPDRQSERIXFhQYHzMhHxwcHz8tLyUzSkFOTUlBSEZSXHZkUldvWEZIZoxob3p9hIWET2ORm4+AmnaBhH//2wBDARYXFx8bHzwhITx/VEhUf39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f3//";

string secondS = "abcdefg2wBDABQODxIPDRQSERIXFh/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/abcdefg";

I want to search firstS to see if it contains any sequence of characters that's in secondS and then replace it. It also needs to be replaced with the number of replaced characters in squared brackets:

[NUMBER-OF-CHARACTERS-REPLACED]

For example, because firstS and secondS both contain "2wBDABQODxIPDRQSERIXFh" and "/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/f39/" they would need to be replaced. So then firstS becomes:

string firstS = "/9j/4AAQSkZJRgABAQEAYABgAAD/[22]QYHzMhHxwcHz8tLyUzSkFOTUlBSEZSXHZkUldvWEZIZoxob3p9hIWET2ORm4+AmnaBhH//2wBDARYXFx8bHzwhITx/VEhUf39[61]f3//";

Hope that makes sense. I think I could do this with Regex, but I don't like the inefficiency of it. Does anyone know of another, faster way?

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