我所做的就是下载2.7.6和3.3.4。Python 3.3.4提供了在环境变量中添加路径的选项，这样就完成了。所以基本上我只是手动添加了Python 2.7.6。

如何……

Start > in the search type in environment select "Edit environment variables to your account"1 Scroll down to Path, select path, click edit. Add C:\Python27; so you should have paths to both versions of Python there, but if you don't this you can easily edit it so that you do..... C:\Python27;C:\Python33; Navigate to the Python27 folder in C:\ and rename a copy of python.exe to python2.exe Navigate to the Python34 folder in C:\ and rename a copy of python.exe to python3.exe Test: open up commmand prompt and type python2 ....BOOM! Python 2.7.6. exit out. Test: open up commmand prompt and type python3 ....BOOM! Python 3.4.3. exit out.

注意:(为了不破坏步骤4和5中的pip命令，将python.exe的副本保存在与重命名文件相同的目录中)

我所做的就是下载2.7.6和3.3.4。Python 3.3.4提供了在环境变量中添加路径的选项，这样就完成了。所以基本上我只是手动添加了Python 2.7.6。

如何……

Start > in the search type in environment select "Edit environment variables to your account"1 Scroll down to Path, select path, click edit. Add C:\Python27; so you should have paths to both versions of Python there, but if you don't this you can easily edit it so that you do..... C:\Python27;C:\Python33; Navigate to the Python27 folder in C:\ and rename a copy of python.exe to python2.exe Navigate to the Python34 folder in C:\ and rename a copy of python.exe to python3.exe Test: open up commmand prompt and type python2 ....BOOM! Python 2.7.6. exit out. Test: open up commmand prompt and type python3 ....BOOM! Python 3.4.3. exit out.

注意:(为了不破坏步骤4和5中的pip命令，将python.exe的副本保存在与重命名文件相同的目录中)

我在windows中有多个版本。 我只是改变了我不是默认版本的exe名称。

Python.exe——> python26.exe python .exe——> pythonw26.exe

至于软件包安装程序，大多数exe安装程序也允许您选择python安装程序来添加软件包。 对于手动安装，检查——prefix选项来定义包应该安装在哪里:

http://docs.python.org/install/index.html#alternate-installation-windows-the-prefix-scheme

安装Python后检查系统环境变量，首先在PATH变量中应该是python3的目录，然后是python2。

最先匹配的路径变量就是Windows使用的路径变量。

一如既往，py -2将在此场景中启动python2。

只有在Python IDE中运行代码才有效

我的windows操作系统上同时安装了Python 2.7和Python 3.3。如果我试图启动一个文件，它通常会在python 2.7 IDE上打开。我如何解决这个问题，是当我选择在python 3.3上运行我的代码时，我打开python 3.3 IDLE(python GUI)，选择文件，用IDLE打开我的文件并保存它。然后，当我运行我的代码时，它运行到我当前打开它的IDLE。反之亦然。

在另一个上面安装最常用的一个(我的例子是3.3)。这将迫使IDLE使用您想要的那个。

或者(来自python3.3 README):

安装多个版本

On Unix and Mac systems if you intend to install multiple versions of Python using the same installation prefix (--prefix argument to the configure script) you must take care that your primary python executable is not overwritten by the installation of a different version. All files and directories installed using "make altinstall" contain the major and minor version and can thus live side-by-side. "make install" also creates ${prefix}/bin/python3 which refers to ${prefix}/bin/pythonX.Y. If you intend to install multiple versions using the same prefix you must decide which version (if any) is your "primary" version. Install that version using "make install". Install all other versions using "make altinstall".

例如，如果你想安装Python 2.6, 2.7和3.3，其中2.7是 主版本，您将在2.7构建目录中执行“make install” 而其他的则是“make altinstall”。