解决：iOS工程配置git忽略文件.gitignore无效的问题

1、打开终端cd到本地仓库，和.git同层（查看隐藏文件）

$ cd project
$ ls -a

2、创建.gitignore文件

$ vim .gitignore

3、键入 "i"，看到下面这个，进入编辑模式

-- INSERT --

4、把下面的这些复制进去

# Created by https://www.gitignore.io/api/objective-c

# Edit at https://www.gitignore.io/?templates=objective-c

### Objective-C ###

# Xcode

#

# gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore & Swift.gitignore

## OS X

#

#DS_Store是mac系统中管理文件夹位置信息的文件

.DS_Store

*/.DS_Store

## vim or gvim每次写完代码的时候，项目中会多出很多*.swp文件

*.swp

## Build generated(编译时产生的文件)

build/

DerivedData/

## Various settings(其他设置)

*.pbxuser

!default.pbxuser

*.mode1v3

!default.mode1v3

*.mode2v3

!default.mode2v3

*.perspectivev3

!default.perspectivev3

xcuserdata/

## Other

*.moved-aside

*.xccheckout

*.xcscmblueprint

## Obj-C/Swift specific

*.hmap

*.ipa

*.dSYM.zip

*.dSYM

# CocoaPods(管理第三方的工具)

#

# We recommend against adding the Pods directory to your .gitignore. However

# you should judge for yourself, the pros and cons are mentioned at:

# https://guides.cocoapods.org/using/using-cocoapods.html#should-i-check-the-pods-directory-into-source-control

Pods/

# Carthage(类似于CocoaPods的管理第三方的工具)

#

# Add this line if you want to avoid checking in source code from Carthage dependencies.

# Carthage/Checkouts

Carthage/Build

# fastlane(自动打包工具集)

#

# It is recommended to not store the screenshots in the git repo. Instead, use fastlane to re-generate the

# screenshots whenever they are needed.

# For more information about the recommended setup visit:

# https://docs.fastlane.tools/best-practices/source-control/#source-control

fastlane/report.xml

fastlane/Preview.html

fastlane/screenshots/**/*.png

fastlane/test_output

# Code Injection(Xcode上的一个插件)

#

# After new code Injection tools there's a generated folder /iOSInjectionProject

# https://github.com/johnno1962/injectionforxcode

iOSInjectionProject/

### Objective-C Patch ###

# End of https://www.gitignore.io/api/objective-c

5、键入 "esc" ，退出编辑模式

6、键入 ":wq" ，保存并退出

到这里，就创建好了".gitignore"文件了！！

7、gitignore规则不生效的解决办法，先把本地缓存删除然后更新

git rm -r --cached .

git add .

git commit -m 'update .gitignore'