Random Numbers and letters using (char)('a'+ number) [duplicate]

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• How can I generate random alphanumeric strings in C#? 27 answers

Hi I would love to google this and find out without asking but IDK what it would be called.

I found this when searching for a way to do random letters and would assume i should be able to use some sort of ascii reference to figure out what number could be added to it to make numbers appear.

so this outputs just weird alphas and question marks when I experimented with it. Does anyone know what this is called or a reference chart. or even better how in c# to make a random numberletter generator like and output of "3f7suf83"

char letter = (char)('a'+num);