core.py 文件源码

def _extract_indices(self, prefix, formdata):
        """
        Yield indices of any keys with given prefix.

        formdata must be an object which will produce keys when iterated.  For
        example, if field 'foo' contains keys 'foo-0-bar', 'foo-1-baz', then
        the numbers 0 and 1 will be yielded, but not neccesarily in order.
        """
        offset = len(prefix) + 1
        for k in formdata:
            if k.startswith(prefix):
                k = k[offset:].split('-', 1)[0]
                if k.isdigit():
                    yield int(k)