一、项目中一直用到了文字转语音的功能，需求也比较简单，就是将一段报警信息通过语音的方式播放出来，之前一直采用cs客户端，利用微软自带的speech语音播放库就可以完成，
1.1 封装winspedk类代码如下：
namespace speak
{
using system;
using system.runtime.compilerservices;
using system.speech.synthesis;
using system.threading;
using speechlib;
public class winspeak
{
#region 属性
private speechsynthesizer speak;
public event errorinfo errorinfoevent;
private thread thvoice;
private string strvoicemsg;
spvoice voice = null;
private static winspeak _intence;
#endregion
private winspeak()
{
voice = new spvoice();
}
#region 方法
public static winspeak _init()
{
if (_intence == null)
_intence = new winspeak();
return _intence;
}
/// <summary>
/// 读语音
/// </summary>
private void speakm()
{
try
{
if (speak != null)
{
this.speak.speakasync(strvoicemsg);
}
}
catch (exception exception)
{
this.errinfo(exception);
}
}
/// <summary>
/// 异步播放文本语音
/// </summary>
/// <param name="msg"></param>
public void beginspeaktext(string msg)
{
try
{
if (speak != null)
{
speak.speakasynccancelall();
speak.dispose();
}
if (thvoice != null && thvoice.threadstate == threadstate.running)
{
thvoice.abort();
}
speak = new speechsynthesizer();
speak.setoutputtodefaultaudiodevice();
strvoicemsg = msg;
//thvoice = new thread(new threadstart(speakm));
//thvoice.start();
speak.speakasync(msg);
gc.collect();
gc.waitforpendingfinalizers();
}
catch (exception exception)
{
this.errinfo(exception);
}
}
/// <summary>
/// 播放文本语音
/// </summary>
/// <param name="msg"></param>
public void speaktext(string msg)
{
try
{
this.speak = new speechsynthesizer();
this.speak.speak(msg);
this.speak.setoutputtonull();
this.speak.dispose();
}
catch (exception exception)
{
this.errinfo(exception);
}
}
/// <summary>
/// speech播放文本合成语音
/// </summary>
/// <param name="msg"></param>
public void speech_speaktext(string msg)
{
try
{
if (voice != null)
{
voice.speak(null, speechvoicespeakflags.svsfpurgebeforespeak);
voice.speak(msg, speechvoicespeakflags.svsflagsasync);
}
}
catch (exception ex)
{
this.errinfo(ex);
}
}
/// <summary>
/// 关闭语音释放资源
/// </summary>
public void speakclose()
{
try
{
if (speak != null)
{
this.speak.speakasynccancelall();
this.speak.dispose();
}
if (voice != null)
{
voice.speak(null, speechvoicespeakflags.svsfpurgebeforespeak);
}
}
catch (exception ex)
{
cglobe_log.error(cglobe_log.getmethodinfo() + ex.message);
}
}
/// <summary>
/// 获取错误信息
/// </summary>
/// <param name="str"></param>
private void errinfo(exception str)
{
if (this.errorinfoevent != null)
{
this.errorinfoevent(str);
}
}
#endregion
~winspeak()
{
try
{
if (speak != null)
{
this.speak.speakasynccancelall();
this.speak.dispose();
}
}
catch (exception exception)
{
//this.errinfo(exception);
}
}
}
}
1.2 调用如下（一个同步播放、一个异步播放）：
private void btntest_click(object sender, eventargs e)
{
try
{
string strsep = txtword.text;
sfbr.winspeak._init().speech_speaktext(strsep);
}
catch (exception ex)
{ }
}
private void button1_click(object sender, eventargs e)
{
try
{
string strsep = txtword.text;
sfbr.winspeak._init().beginspeaktext(strsep);
}
catch (exception ex)
{ }
}
二、 最近客户提出需求需要在bs系统实现文字语音播放的功能，因不能接入外网不能调用第三方服务等，最后想到了一个解决方案:先把文字转化为音频文件，再把音频文件以流的形式推送到bs端进行播放；
2.1 同样可以利用微软自带的speech语音播放库将一段文本转化为音频文件：
2.2 封装 speechservice文字转换音频文件类
public class speechservice
{
private static speechsynthesizer synth = null;
/// <summary>
/// 返回一个speechsynthesizer对象
/// </summary>
/// <returns></returns>
private static speechsynthesizer getspeechsynthesizerinstance()
{
if (synth == null)
{
synth = new speechsynthesizer();
}
return synth;
}
/// <summary>
/// 保存语音文件
/// </summary>
/// <param name="text"></param>
public static void savemp3(string strfilename,string sptext)
{
synth = getspeechsynthesizerinstance();
synth.rate = 1;
synth.volume = 100;
synth.setoutputtowavefile(strfilename);
synth.speak(sptext);
synth.setoutputtonull();
}
}
2.3 接下来就是将音频文件以文件流的形式推送到前端播放：
public async task<actionresult> playwav(string id,string sptext)
{
string strpath = server.mappath("~\\mp4\\" + id + ".wav");
speechservice.savemp3(strpath, sptext);
try
{
using (filestream filestream = new filestream(strpath, filemode.open))
{
byte[] filebyte = new byte[filestream.length];
filestream.seek(0, seekorigin.begin);
filestream.read(filebyte, 0, (int)filestream.length);
long fsize = filestream.length;
long startbyte = 0;
long endbyte = fsize - 1;
int statuscode = 200;
if ((request.headers["range"] != null))
{
//get the actual byte range from the range header string, and set the starting byte.
string[] range = request.headers["range"].split(new char[] { '=', '-' });
startbyte = convert.toint64(range[1]);
if (range.length > 2 && range[2] != "") endbyte = convert.toint64(range[2]);
//if the start byte is not equal to zero, that means the user is requesting partial content.
if (startbyte != 0 || endbyte != fsize - 1 || range.length > 2 && range[2] == "")
{ statuscode = 206; }//set the status code of the response to 206 (partial content) and add a content range header.
}
long dessize = endbyte - startbyte + 1;
//headers
response.statuscode = statuscode;
response.contenttype = "audio/mpeg";
response.addheader("content-accept", response.contenttype);
response.addheader("content-length", dessize.tostring());
response.addheader("content-range", string.format("bytes {0}-{1}/{2}", startbyte, endbyte, fsize));
return file(filebyte, response.contenttype);
}
}
catch (exception ex)
{
throw;
}
}
注意：返回的必须为异步（ async task）不然会报错，因为文字音频转换涉及到异步调用
2.4 前端展示
2.5 运行截图如下：
bs实现文字音频调用demo地址如下：
https://github.com/lxshwyan/speechbsdemo.git
黄山市民网：https://www.huangshanshimin.com/
