find matching text and replace next line

Question

I\'m trying to find a line in a file and replace the next line with a specific value. I tried sed, but it seems to not like the \\n. How else can this be done?

The f

Answer 1

It works. Additionaly is interested to mention that if you write,

sed '/ConnectionString<\/key>/!b;n;n;cchanged_value' file

Note the two n's, it replaces after two lines and so forth.