git 刪除誤上傳的.idea文件

問題：
提交項目的時候忘記添加.gitignore文件，誤上傳了文件(如.idea)如何解決？(本文以.idea文件夾舉例)

1.將項目文件拉取下來

git pull origin master

2.添加須要過濾的文件

a. 若是你有.gitignore文件，可是沒添加誤上傳的文件夾(如.idea)
新起一行添加  .idea/
b. 若是你沒有.gitignore文件，在你的項目裏建立一個.gitignore的文件
將下面的文本放入便可

通用.gitignore文件

# Initially taken from Github's Python gitignore file

# Byte-compiled / optimized / DLL files
__pycache__/
*.py[cod]
*$py.class
__pycache__
# C extensions
*.so
.DS_Store
.idea/
# Distribution / packaging
.Python
build/
develop-eggs/
dist/
downloads/
eggs/
.eggs/
lib/
lib64/
parts/
sdist/
var/
wheels/
*.egg-info/
.installed.cfg
*.egg
MANIFEST

# PyInstaller
#  Usually these files are written by a python script from a template
#  before PyInstaller builds the exe, so as to inject date/other infos into it.
*.manifest
*.spec

# Installer logs
pip-log.txt
pip-delete-this-directory.txt

# Unit test / coverage reports
htmlcov/
.tox/
.nox/
.coverage
.coverage.*
.cache
nosetests.xml
coverage.xml
*.cover
.hypothesis/
.pytest_cache/

# Translations
*.mo
*.pot

# Django stuff:
*.log
local_settings.py
db.sqlite3

# Flask stuff:
instance/
.webassets-cache

# Scrapy stuff:
.scrapy

# Sphinx documentation
docs/_build/

# PyBuilder
target/

# Jupyter Notebook
.ipynb_checkpoints

# IPython
profile_default/
ipython_config.py

# pyenv
.python-version

# celery beat schedule file
celerybeat-schedule

# SageMath parsed files
*.sage.py

# Environments
.env
.venv
env/
venv/
ENV/
env.bak/
venv.bak/

# Spyder project settings
.spyderproject
.spyproject

# Rope project settings
.ropeproject

# mkdocs documentation
/site

# mypy
.mypy_cache/
.dmypy.json
dmypy.json

# Pyre type checker
.pyre/

data/
model/

3.打開項目終端執行命令

# 刪除github上的誤上傳文件.idea 
git rm -rf --cached .idea

4.提交.gitignore文件

git add .gitignore

5.上傳

git commit -m '忽略idea'
git push -u origin master