Issue #19198: Improved cross-references in the cgi module documentation.
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@ -97,7 +97,7 @@ standard input, it should be instantiated only once.
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The :class:`FieldStorage` instance can be indexed like a Python dictionary.
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It allows membership testing with the :keyword:`in` operator, and also supports
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the standard dictionary method :meth:`keys` and the built-in function
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the standard dictionary method :meth:`~dict.keys` and the built-in function
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:func:`len`. Form fields containing empty strings are ignored and do not appear
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in the dictionary; to keep such values, provide a true value for the optional
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*keep_blank_values* keyword parameter when creating the :class:`FieldStorage`
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@ -119,30 +119,32 @@ string::
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Here the fields, accessed through ``form[key]``, are themselves instances of
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:class:`FieldStorage` (or :class:`MiniFieldStorage`, depending on the form
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encoding). The :attr:`value` attribute of the instance yields the string value
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of the field. The :meth:`getvalue` method returns this string value directly;
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it also accepts an optional second argument as a default to return if the
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requested key is not present.
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encoding). The :attr:`~FieldStorage.value` attribute of the instance yields
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the string value of the field. The :meth:`~FieldStorage.getvalue` method
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returns this string value directly; it also accepts an optional second argument
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as a default to return if the requested key is not present.
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If the submitted form data contains more than one field with the same name, the
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object retrieved by ``form[key]`` is not a :class:`FieldStorage` or
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:class:`MiniFieldStorage` instance but a list of such instances. Similarly, in
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this situation, ``form.getvalue(key)`` would return a list of strings. If you
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expect this possibility (when your HTML form contains multiple fields with the
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same name), use the :func:`getlist` function, which always returns a list of
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values (so that you do not need to special-case the single item case). For
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example, this code concatenates any number of username fields, separated by
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commas::
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same name), use the :meth:`~FieldStorage.getlist` method, which always returns
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a list of values (so that you do not need to special-case the single item
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case). For example, this code concatenates any number of username fields,
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separated by commas::
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value = form.getlist("username")
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usernames = ",".join(value)
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If a field represents an uploaded file, accessing the value via the
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:attr:`value` attribute or the :func:`getvalue` method reads the entire file in
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memory as bytes. This may not be what you want. You can test for an uploaded
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file by testing either the :attr:`filename` attribute or the :attr:`!file`
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:attr:`~FieldStorage.value` attribute or the :meth:`~FieldStorage.getvalue`
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method reads the entire file in memory as bytes. This may not be what you
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want. You can test for an uploaded file by testing either the
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:attr:`~FieldStorage.filename` attribute or the :attr:`~FieldStorage.file`
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attribute. You can then read the data at leisure from the :attr:`!file`
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attribute (the :func:`read` and :func:`readline` methods will return bytes)::
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attribute (the :func:`~io.RawIOBase.read` and :func:`~io.IOBase.readline`
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methods will return bytes)::
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fileitem = form["userfile"]
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if fileitem.file:
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@ -155,8 +157,8 @@ attribute (the :func:`read` and :func:`readline` methods will return bytes)::
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If an error is encountered when obtaining the contents of an uploaded file
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(for example, when the user interrupts the form submission by clicking on
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a Back or Cancel button) the :attr:`done` attribute of the object for the
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field will be set to the value -1.
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a Back or Cancel button) the :attr:`~FieldStorage.done` attribute of the
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object for the field will be set to the value -1.
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The file upload draft standard entertains the possibility of uploading multiple
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files from one field (using a recursive :mimetype:`multipart/\*` encoding).
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@ -223,8 +225,8 @@ Therefore, the appropriate way to read form data values was to always use the
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code which checks whether the obtained value is a single value or a list of
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values. That's annoying and leads to less readable scripts.
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A more convenient approach is to use the methods :meth:`getfirst` and
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:meth:`getlist` provided by this higher level interface.
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A more convenient approach is to use the methods :meth:`~FieldStorage.getfirst`
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and :meth:`~FieldStorage.getlist` provided by this higher level interface.
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.. method:: FieldStorage.getfirst(name, default=None)
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