how to validate the email in stored procedure

create function IsValidEmail
(
    @email_address varchar(255)
) returns bit
as begin

    declare @ErrMsg varchar(max) = ''

    IF CHARINDEX(' ',LTRIM(RTRIM(@email_address))) > 0
        set @ErrMsg = @ErrMsg + CHAR(13) + 'No Spaces Allowed'

    IF LEFT(LTRIM(@email_address),1) = '@'
        set @ErrMsg = @ErrMsg + CHAR(13) + '@ can not be the first character of an email address'

    IF LEFT(LTRIM(@email_address),1) = '.'
        set @ErrMsg = @ErrMsg + CHAR(13) + '. can not be the first character of an email address'


    if RIGHT(RTRIM(@email_address),1) = '.'
        set @ErrMsg = @ErrMsg + CHAR(13) + '. can not be the last character of an email address'

    if LEN(LTRIM(RTRIM(@email_address ))) - LEN(REPLACE(LTRIM(RTRIM(@email_address)),'@','')) <> 1
        set @ErrMsg = @ErrMsg + CHAR(13) + ' Add @'

    If( CHARINDEX('.',REVERSE(RTRIM(LTRIM(@email_address)))) > 4 )
        set @ErrMsg = @ErrMsg + CHAR(13) + '. Add domain name ex: .com'

    if( (CHARINDEX('.@',@email_address ) > 0 OR CHARINDEX('..',@email_address ) > 0
        OR CHARINDEX('@@',@email_address ) > 0
        OR CHARINDEX('#',@email_address ) > 0
        OR CHARINDEX('^',@email_address ) > 0
        OR CHARINDEX('&',@email_address ) > 0
        OR CHARINDEX('*',@email_address ) > 0
        OR CHARINDEX('(',@email_address ) > 0
        OR CHARINDEX(')',@email_address ) > 0
        OR CHARINDEX('+',@email_address ) > 0
        OR CHARINDEX('=',@email_address ) > 0)
    )
        set @ErrMsg = @ErrMsg + CHAR(13) + 'invalid character'

    declare @Result bit

    if @ErrMsg = ''
        set @Result = 1 --it IS valid
    else
        set @result = 0

    return @Result
end

go