微信小程序：分享转发至好友

wxml: 

js:

  // 分享
  onShareAppMessage: function () {
    var that = this;
    var title = '分享标题';
    var cover_img = '/images/share/share.jpg';
    return {
      title: title,
      path: '/pages/login/login',
      imageUrl: cover_img,
      success: function (res) { }
    }
  },

wxss: 

.share_btn {
  position: absolute;
  top: 1160rpx;
  left: 74rpx;
  height: 50rpx;
  width: 228rpx;
  opacity: 0;
}