Python環境之虛擬環境virtualenv的安裝和使用

1、安裝

pip install virtualenv
pip install virtualenvwrapper

2、配置

# 1、創建目錄用來存放虛擬環境
mkdir $HOME/.virtualenv

# 2、virtualenvwrapper.sh文件的路徑
find / -name virtualenvwrapper.sh
# 參考答案 /usr/local/bin/virtualenvwrapper.sh

# 3、查找Python3的路徑
which python3
# 參考答案 /Library/Frameworks/Python.framework/Versions/3.6/bin/python3

# 4、打開~/.bashrc文件，並添加如下：
export WORKON_HOME=$HOME/.virtualenvs
export VIRTUALENVWRAPPER_PYTHON=/Library/Frameworks/Python.framework/Versions/3.6/bin/python3
source /usr/local/bin/virtualenvwrapper.sh

# 5、運行
source ~/.bashrc

3、使用

# 創建虛擬環境 指定python3
mkvirtualenv -p python3 虛擬環境名稱
# 查看虛擬環境
workon
# 進入虛擬環境
workon 虛擬環境名稱
# 刪除虛擬環境
deactivate

重點！！！:

如果你的環境是Python3, 重載以後,可能會出現一下的問題

/usr/bin/python: No module named virtualenvwrapper
virtualenvwrapper.sh: There was a problem running the initialization hooks.

If Python could not import the module virtualenvwrapper.hook_loader,
check that virtualenvwrapper has been installed for
VIRTUALENVWRAPPER_PYTHON=/usr/bin/python and that PATH is
set properly.

解決辦法:

1、修改 virtualenvwrapper.sh

vim /usr/local/bin/virtualenvwrapper.sh

2、找到 virtualenvwrapper.sh 中如下代碼

# Setup:
#
#  1. Create a directory to hold the virtual environments.
#     (mkdir $HOME/.virtualenvs).
#  2. Add a line like "export WORKON_HOME=$HOME/.virtualenvs"
#     to your .bashrc.
#  3. Add a line like "source /path/to/this/file/virtualenvwrapper.sh"
#     to your .bashrc.
#  4. Run: source ~/.bashrc
#  5. Run: workon
#  6. A list of environments, empty, is printed.
#  7. Run: mkvirtualenv temp
#  8. Run: workon
#  9. This time, the "temp" environment is included.
# 10. Run: workon temp
# 11. The virtual environment is activated.
#

# Locate the global Python where virtualenvwrapper is installed.

if [ "$VIRTUALENVWRAPPER_PYTHON" = "" ] then
    VIRTUALENVWRAPPER_PYTHON="$(command \which python)"
fi

3、註釋下面加上一行，修改 VIRTUALENVWRAPPER_PYTHON 的默認值

# Locate the global Python where virtualenvwrapper is installed.

VIRTUALENVWRAPPER_PYTHON=/usr/bin/python3

if [ "$VIRTUALENVWRAPPER_PYTHON" = "" ] then
    VIRTUALENVWRAPPER_PYTHON="$(command \which python)"
fi

4、重新加載 virtualenvwrapper.sh

./usr/local/bin/virtualenvwrapper.sh

5、重新加載 .bashrc

source ~/.bashrc