What will be the output of

DECLARE @Name AS VARCHAR(30) ='dotnetfunda!!>$:niceforum'
SELECT NAME = SUBSTRING(@Name,1,ISNULL(NULLIF(PATINDEX('%[^A-Za-z0-9]%',@Name),0)-1,LEN(@Name)))

By using the PATINDEX we are finding the pattern and removing the junk characters and then limiting the subtring value by specifying the length so that we can obtain the substring before the special junk characters.