javascript - Regular Expression for checking at least one alphabet or number -

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i want regular expression checks if string contains allowed characters. allowed characters alphanumeric , special characters (),#\/\-. used expression, , working fine. 

/^([a-za-z0-9 .(),#\/\-]*)+$/

now don't want string start space or disallowed characters, can have space in middle. also, string may not consist of special characters; should have @ least 1 alphanumeric character.

can me understand how adapt regex using check these additional constraints?

 ^(?=[a-za-z0-9])([a-za-z0-9 .(),#\/-]*)+$

this should it.


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