【笔记】歌词显示问题

上节写了如何从千千静听服务器下载歌词，这节说说如何让歌词显示出来

　　首先是分析歌词文件，分析出不同时间对于的歌词

1、定义一个歌词行的类LrcLineItem

public class LrcLineItem
{
public string TimeString { get; set; }
public string Text { get; set; }
public double Time { get; set; }

public LrcLineItem(string text, double time)
{
this.Text = text;
this.Time = time;

//[02:13.60]歌词
int timeint = (int)this.Time;
this.TimeString = "[" + (timeint / 60).ToString("d2") + ":" + (timeint % 60).ToString("d2") + (Time - timeint).ToString("f2").Substring(1, 3) + "]" + Text;
}

public override string ToString()
{
return this.TimeString;
}
}

然后计算出歌词中所有的不同时间对于的歌词存放到LrcLineItem数组中

下面定义LrcAnalyze类

public class LrcAnalyze
{
string title;
string artist;
string album;
string content;
List<LrcLineItem> lrcList;

public LrcLineItem[] lrcs { get; set; }

public LrcAnalyze(string filepath)
{
lrcList = new List<LrcLineItem>();
using (StreamReader reader = new StreamReader(filepath, Encoding.UTF8))
{
content = reader.ReadToEnd();
}
Analyze();
}

private void Analyze()
{
StringReader reader = new StringReader(content);

string lineStr = reader.ReadLine();
while (lineStr !=null)
{
if (lineStr != null && lineStr.Length > 3)
{
switch (lineStr.Substring(1, 2))
{
case "ti":
title = lineStr.Substring(4, lineStr.Length - 5);
break;
case "ar":
artist = lineStr.Substring(4, lineStr.Length - 5);
break;
case "al":
album = lineStr.Substring(4, lineStr.Length - 5);
break;
default:
GetLrcStr(lineStr);
break;
}
}
lineStr = reader.ReadLine();

}
//排序（冒泡）
SortLrcLine();
}

private void GetLrcStr(string lineStr)
{
int num = (lineStr.LastIndexOf(']') + 1) / 10;
string text = lineStr.Substring(num * 10);

try
{
for (int i = 0; i < num; i++)
{
string timestr = lineStr.Substring(i * 10 + 1, 8);
double time = Convert.ToDouble(timestr.Substring(0, 2)) * 60 + Convert.ToDouble(timestr.Substring(3, 5));
lrcList.Add(new LrcLineItem(text, time));
}
}
catch(FormatException)
{
}
}

private void SortLrcLine()
{
lrcs = lrcList.ToArray();
for (int i = 0; i < lrcs.Length - 1; i++)
{
for (int j = i + 1; j < lrcs.Length; j++)
{
if (lrcs[i].Time > lrcs[j].Time)
{
LrcLineItem temp = lrcs[j];
lrcs[j] = lrcs[i];
lrcs[i] = temp;
}
}

}
}

//获得相应时间的歌词，返回索引
public int GetIndex(double time)
{
for (int i = 0; i < lrcs.Length; i++)
{
if (lrcs[i].Time > time)
{
return i - 1;
}
}
return lrcs.Length - 1;
}

//返回多行歌词（count*2+1行）
public string[] GetLrcStrings(int count, double time)
{
int index = GetIndex(time);

string[] lrcstrings = new string[count * 2 + 1];
for (int i = 0; i < count; i++)
{
if (index - count + i > 0)
lrcstrings[i] = lrcs[index - count + i].Text;
else
lrcstrings[i] = string.Empty;
}
lrcstrings[count] = lrcs[index].Text;
for (int i = 0; i < count; i++)
{
if (index + i < lrcs.Length)
lrcstrings[count + i + 1] = lrcs[index + i].Text;
else
lrcstrings[i] = string.Empty;
}
return lrcstrings;
}
}

好了，歌词的分析算是完成了，接下来实践一下

　　1、创建一个WinForm窗体，添加7个Label控件分别是Label1，Labe2l，Label3，Label4，Label5，Label6，Label7，用于显示歌词，其中Label4的颜色设为红色，其他设为白色

　　2、添加一个按钮Play，用于开始播放音乐

　　3、定义两个文件Lrc和Mp3，这里的Mp3文件用之前讲的 AxWindowsMediaPlayer播放

string musicfile = @"G:\Music\郭峰 - 心甘情愿.mp3";
string lrcfile = @"G:\Music\郭峰 - 心甘情愿.lrc";

　　4、添加一个计时器timer1，用于计算当前播放，时间间隔设为500，没半秒刷新一次歌词，添加触发事件

　　5、为axWindowsMediaPlayer1添加一个事件函数PositionChange，当进度条改变时，time也相应改变

代码如下

public partial class Form1 : Form
{
double time = 0;        //当前播放时间
LrcAnalyze lrc;            //歌词信息

string musicfile = @"G:\Music\郭峰 - 心甘情愿.mp3";
string lrcfile = @"G:\Music\郭峰 - 心甘情愿.lrc";

public Form1()
{
InitializeComponent();
lrc = new LrcAnalyze(lrcfile);
}

private void timer1_Tick(object sender, EventArgs e)
{
this.time = this.time + 0.5;
//更新UI
string[] strs = this.lrc.GetLrcStrings(3, time);
this.label1.Text = strs[0];
this.label2.Text = strs[1];
this.label3.Text = strs[2];
this.label4.Text = strs[3];
this.label5.Text = strs[4];
this.label6.Text = strs[5];
this.label7.Text = strs[6];
}

private void axWindowsMediaPlayer1_PositionChange(object sender, AxWMPLib._WMPOCXEvents_PositionChangeEvent e)
{
this.time = e.newPosition;
}

private void btnPlay_Click(object sender, EventArgs e)
{
this.axWindowsMediaPlayer1.URL = musicfile;
this.axWindowsMediaPlayer1.Ctlcontrols.play();
this.timer1.Start();
}
}