var str = "aaabbbcccdddeeefff";
str = str.match(/aaa(\S*)fff/)[1];
alert(str);//结果bbbcccdddeee

实际运用 获取目录内容并将文件夹名称提取出来

    const files = require.context('../../components/bar', true, /.vue$/).keys();
    console.log(files)
    files.forEach((type) => {
      this.comps.push(type.match(/.\/(\S*)\/index.vue/)[1])
    });
    console.log(this.comps)

提取前

['./bar1/index.vue', './bar2/index.vue', './bar3/index.vue']

提取后

 ['bar1', 'bar2', 'bar3']