语音识别这个功能属于高级功能，必须微信实名认证后才能实现，认证费用300元/年，如果你作为开发者可以申请测试帐号，也是可以的。首先建立一个微信消息类，这个类比之前多了一个属性。
class wxmessage
{ public string FromUserName { get; set; } public string ToUserName { get; set; } public string MsgType { get; set; } public string EventName { get; set; } public string Content { get; set; } public string Recognition { get; set; } public string EventKey { get; set; } }
音识别是微信自带的功能，非常强大无需我们做过多的操作：
protected void Page_Load(object sender, EventArgs e)
{ wxmessage wx = GetWxMessage(); string res = "";if (!string.IsNullOrEmpty(wx.EventName) && wx.EventName.Trim() == "subscribe")
{//刚关注时的时间，用于欢迎词 string content = ""; content = "/:rose欢迎北京永杰友信科技有限公司/:rose\n直接回复“你好”"; res = sendTextMessage(wx, content); } else { if (wx.MsgType == "text" && wx.Content == "你好") { res = sendTextMessage(wx, "你好,欢迎使用北京永杰友信科技有限公司公共微信平台!"); } else if (wx.MsgType == "voice")//识别消息类型为语音 { res = sendTextMessage(wx, wx.Recognition);//wx.Recognition就是语音识别的结果了，我们直接引用，以文本形式反馈就OK了}
else { res = sendTextMessage(wx, "你好,未能识别消息!"); } }Response.Write(res);
}private wxmessage GetWxMessage()
{ wxmessage wx = new wxmessage(); StreamReader str = new StreamReader(Request.InputStream, System.Text.Encoding.UTF8); XmlDocument xml = new XmlDocument(); xml.Load(str); wx.ToUserName = xml.SelectSingleNode("xml").SelectSingleNode("ToUserName").InnerText; wx.FromUserName = xml.SelectSingleNode("xml").SelectSingleNode("FromUserName").InnerText; wx.MsgType = xml.SelectSingleNode("xml").SelectSingleNode("MsgType").InnerText; if (wx.MsgType.Trim() == "text") { wx.Content = xml.SelectSingleNode("xml").SelectSingleNode("Content").InnerText; } if (wx.MsgType.Trim() == "event") { wx.EventName = xml.SelectSingleNode("xml").SelectSingleNode("Event").InnerText; } if (wx.MsgType.Trim() == "voice")//如果是语音消息的话就把识别结果赋值给实体类的相应属性Recognition { wx.Recognition = xml.SelectSingleNode("xml").SelectSingleNode("Recognition").InnerText; } return wx; } /// <summary> /// 发送文字消息 /// </summary> /// <param name="wx">获取的收发者信息 /// <param name="content">内容 /// <returns></returns> private string sendTextMessage(wxmessage wx, string content) { string res = string.Format(@" ", wx.FromUserName, wx.ToUserName, DateTime.Now, content); return res; }