1. Install gulp globally:
$ npm install --global gulp
2. Install gulp in your project devDependencies:
$ npm install --save-dev gulp
3. Create a gulpfile.js at the root of your project:
var gulp = require('gulp');
gulp.task('default', function() {
  // place code for your default task here
});
4. Run gulp:
$ gulp
The default task will run and do nothing.
To run individual tasks, use gulp <task> <othertask>.
在项目的根目录新建gulpfile.js,require需要的module
var gulp = require('gulp'),
    minifycss = require('gulp-minify-css'),
    concat = require('gulp-concat'),
    uglify = require('gulp-uglify'),
    rename = require('gulp-rename'),
    del = require('del');
压缩css
gulp.task('minifycss', function() {
    return gulp.src('src/*.css')      //压缩的文件
        .pipe(gulp.dest('minified/css'))   //输出文件夹
        .pipe(minifycss());   //执行压缩
});
压缩js
gulp.task('minifyjs', function() {
return gulp.src('src/*.js')
.pipe(concat('main.js'))    //合并所有js到main.js
.pipe(gulp.dest('minified/js'))    //输出main.js到文件夹
.pipe(rename({suffix: '.min'}))   //rename压缩后的文件名
.pipe(uglify())    //压缩
.pipe(gulp.dest('minified/js'));  //输出
});
执行压缩前,先删除文件夹里的内容
gulp.task('clean', function(cb) {
del(['minified/css', 'minified/js'], cb)
});
默认命令,在cmd中输入gulp后,执行的就是这个命令
gulp.task('default', ['clean'], function() {
gulp.start('minifycss', 'minifyjs');
});
