ios开发学习--歌词处理--解析lrc文件

 1 //
 2 //  LyricsAnalysis.h
 3 //  08-10-MusicPlayer
 4 //
 5 //  Created by Ibokan on 15/8/21.
 6 //  Copyright (c) 2015年 Crazy凡. All rights reserved.
 7 //
 8 
 9 #import <Foundation/Foundation.h>
10 
11 @interface LyricsAnalysis : NSObject
12 @property (nonatomic,strong)NSString *ar;//演唱
13 @property (nonatomic,strong)NSString *ti;//歌曲名
14 @property (nonatomic,strong)NSString *al;//专辑名
15 @property (nonatomic,strong)NSString *by;//歌词作者
16 @property (nonatomic,strong)NSString *t_time;//歌曲总时长
17 @property (nonatomic,strong)NSMutableArray *lrcArrayTime;//时间数组
18 @property (nonatomic,strong)NSMutableArray *lrcArrayStr;//歌词数组
19 
20 - (instancetype)init;
21 - (instancetype)initWithFileName:(NSString *)name ofType:(NSString *)type;
22 - (instancetype)initWithFilePath:(NSString *)filePath;
23 - (void)lyricsAnalysisWithFileName:(NSString *)name ofType:(NSString *)type;
24 - (void)lyricsAnalysisWithFilePath:(NSString *)filePath;
25 @end

 1 //
 2 //  LyricsAnalysis.m
 3 //  08-10-MusicPlayer
 4 //
 5 //  Created by Ibokan on 15/8/21.
 6 //  Copyright (c) 2015年 Crazy凡. All rights reserved.
 7 //
 8 
 9 #import "LyricsAnalysis.h"
10 
11 
12 @interface LyricsAnalysis ()
13 @property double offset;//歌词时间调整变量
14 @end
15 @implementation LyricsAnalysis
16 
17 //初始化
18 - (instancetype)init
19 {
20     self = [super init];
21     if (self) {
22         self.ar = [[NSString alloc]init];
23         self.ti = [[NSString alloc]init];
24         self.by = [[NSString alloc]init];
25         self.al = [[NSString alloc]init];
26         self.offset = 0;
27         self.t_time = [[NSString alloc]init];//歌曲总时长单位（s）
28         self.lrcArrayStr = [[NSMutableArray alloc]init];//歌词数组初始化
29         self.lrcArrayTime = [[NSMutableArray alloc]init];//时间数组初始化
30     }
31     return self;
32 }
33 //带文件名的初始化
34 - (instancetype)initWithFileName:(NSString *)name ofType:(NSString *)type
35 {
36     self = [self init];
37     [self lyricsAnalysisWithFileName:name ofType:type];
38     return self;
39 }
40 //带文件路径的初始化
41 - (instancetype)initWithFilePath:(NSString *)filePath
42 {
43     self = [self init];
44     [self lyricsAnalysisWithFilePath:filePath];
45     return self;
46 }
47 //处理文件名歌词
48 - (void)lyricsAnalysisWithFileName:(NSString *)name ofType:(NSString *)type
49 {
50     [self lyricsAnalysisWithFilePath:[[NSBundle mainBundle] pathForResource:name ofType:type]];//构建filepath
51 }
52 //处理文件路径
53 - (void)lyricsAnalysisWithFilePath:(NSString *)filePath
54 {
55     NSString *strlrc = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];
56     NSMutableArray * arraylrc = [[NSMutableArray alloc] initWithArray:[strlrc componentsSeparatedByString:@"\n"]];
57     NSArray *StrToInt = [NSArray arrayWithObjects:@"ar",@"ti",@"al",@"by",@"of",@"t_",nil];//NSString  switch 配置
58     BOOL flag = YES;
59     while(flag)
60     {
61         NSString *temp = arraylrc[0];
62         switch ((int)[StrToInt indexOfObject:[temp substringWithRange:NSMakeRange(1, 2)]])
63         {
64             case 0:self.ar = [[temp substringFromIndex:4]stringByReplacingOccurrencesOfString:@"]" withString:@"\0"];break;
65             case 1:self.ti = [[temp substringFromIndex:4]stringByReplacingOccurrencesOfString:@"]" withString:@"\0"];break;
66             case 2:self.al = [[temp substringFromIndex:4]stringByReplacingOccurrencesOfString:@"]" withString:@"\0"];break;
67             case 3:self.by = [[temp substringFromIndex:4]stringByReplacingOccurrencesOfString:@"]" withString:@"\0"];break;
68             case 4:self.offset = [[[temp substringFromIndex:8] stringByReplacingOccurrencesOfString:@"]" withString:@"\0"] doubleValue];break;
69             case 5:self.t_time = [[temp substringFromIndex:9] stringByReplacingOccurrencesOfString:@")]" withString:@"\0"];break;
70             default:flag = NO; break;
71         }
72         flag?[arraylrc removeObjectAtIndex:0]:nil;//判断是否需要移除已经被读取的信息（是歌词则不移除）
73     }// lrc时间的格式分3种:[mm:ss.SS]、[mm:ss:SS]、[mm:ss];第一种是标准形式，后面两种存在但是不标准;先把时间字符串按照“:”拆分，生成{mm ss.SS}、{mm ss SS}、{mm ss};对于1、3,直接取doubleValue即可;注意分钟*60;对于第二种情况需要单独处理SS(毫秒)位；
74     for (NSString *str in arraylrc) {
75         NSArray * ArrayTemp = [str componentsSeparatedByString:@"]"];//分割每一句歌词
76         for(int j = 0 ; j < ArrayTemp.count -1 ;j++)
77         {
78             NSArray * Arraytime = [[ArrayTemp[j] substringFromIndex:1] componentsSeparatedByString:@":"];//分割时间字符串
79             double timedouble = [Arraytime[0] doubleValue]*60.0 + [Arraytime[1] doubleValue];//处理分钟和秒
80             timedouble += Arraytime.count > 2 ? [[[NSString alloc]initWithFormat:@"0.%@",Arraytime[2]] doubleValue]:0;//处理毫秒位
81             timedouble += (self.offset / 1000.0);//时间调整
82             timedouble = timedouble > 0 ? timedouble : 0;//避免因为时间调整导致的时间<0
83             int i = 0;
84             while (i < self.lrcArrayTime.count && [self.lrcArrayTime[i++] doubleValue] < timedouble);//查找当前歌词的插入位置
85             [self.lrcArrayTime insertObject:[[NSString alloc]initWithFormat:@"%lf",timedouble] atIndex:i];//插入时间数组
86             [self.lrcArrayStr insertObject:ArrayTemp[ArrayTemp.count-1] atIndex:i];//插入歌词数组
87         }
88     }
89 }
90 @end