forms.py

python web programming 部分

class FormsMixin:

    def DropDown(self, tbl, valcol, descol, name="pulldown",
                default="Please make a selection",
                selected=None, ordercol=None, autosubmit=None):

        """Create a dropdown selector from two columns of a database table.

        Note that column aliasing is used to give fixed attribute names to
        the columns retrieved, so this algorithm works with two different
        database columns or the same one for both value and description."""

        td = dtuple.TupleDescriptor([("ValCol",), ("DesCol",)])
        if autosubmit:
            auto = """OnChange="submit(this.parent)"""
        else:
            auto = ""
        result = ["""<SELECT NAME="%s" %s ">""" % (name, auto)]
        result.append(self.Option("", default))
        stmt = "SELECT %s, %s FROM %s" % (valcol, descol, tbl)
        if ordercol:
            stmt += " ORDER BY %s" % ordercol
        # print stmt
        self.cursor.execute(stmt)
        rows = self.cursor.fetchall()
        for row in rows:
            row = dtuple.DatabaseTuple(td, row)
            result.append(self.Option(row.ValCol, row.DesCol))
        result.append("</SELECT>\n")
        return "\n".join(result)

    def Option(self, val, dsc):
        return """<OPTION VALUE="%s">%s""" % (val, dsc)