响应UIWebView的点击事件(播放声音)，从数据库中取出声音保存在本地。
在iPhone开发中经常会遇到需要在UIWebView中点击按钮并进行相应的操作，比如点击按钮播放声音等，以下是代码，并从数据库中取出声音数据，以文件的形式保存在本地。

- (BOOL)webView:(UIWebView*)webView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType {...AppDelegate *appDelegate=(...AppDelegate *)[[UIApplication sharedApplication] delegate];if (navigationType == UIWebViewNavigationTypeLinkClicked) {NSURL *URL = [request URL];NSLog([URL scheme]);NSLog([URL absoluteString]);//.......code here and call the delegate methodNSAutoreleasePool *pool=[[NSAutoreleasePool alloc] init];BOOL audioResult=FALSE;NSFileManager *fileManager = [NSFileManager defaultManager];//check if file existed in cache folderNSArray *cache = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);NSString *cachePath = [cache objectAtIndex:0] ;NSString *filepath ;filepath=[cachePath stringByAppendingPathComponent:[audioId stringByAppendingString:@".wav"]];if ([fileManager fileExistsAtPath:filepath]==YES){[self playVoice:filepath];}else{audioResult=[appDelegate saveAudio:audioId];if (audioResult==YES){//NSLog(@"Speak the audio by the path=%@",filepath);[self playVoice:filepath];}}[pool release];[appDelegate saveAudio:gotFM];}

-(BOOL)saveAudio:(NSString *)key{NSLog(key);BOOL saveSuccess=FALSE;NSString *dbPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"testVoice.db"];if(sqlite3_open([dbPath UTF8String], &database_voice) == SQLITE_OK){NSString *sqlString=[NSString stringWithFormat:@"select * from tb_voice where id='%@'",key];NSLog(sqlString);const char *sql_char=[sqlString UTF8String];//prepare the select statementint returnValue = sqlite3_prepare_v2(database_voice, sql_char, -1, &selectStatement, NULL);if(returnValue == SQLITE_OK){//loop all the rows returned by the query.if(sqlite3_step(selectStatement) == SQLITE_ROW){NSFileManager *fileManager = [NSFileManager defaultManager];NSArray *cache = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);NSString *cachePath = [cache objectAtIndex:0] ;NSString *filename=[NSString stringWithUTF8String:(char *)sqlite3_column_text(selectStatement, 0)];////NSLog(filename);NSData *fileData=[NSData dataWithBytes:sqlite3_column_blob(selectStatement, 2) length:sqlite3_column_bytes(selectStatement,2)];//save the file data//check NSString *filepath = [cachePath stringByAppendingPathComponent:filename];filepath=[filepath stringByAppendingString:@".wav"];if ([fileManager createDirectoryAtPath:cachePath attributes:nil]==NO){////NSLog(@"fileManager createDirectoryAtPath:cachePath attributes:nil");}if ([fileData writeToFile:filepath atomically:YES]){saveSuccess=TRUE;//NSLog(@"saveSuccess");////NSLog(@"returnValue");}else{//NSLog(@"save Fail");}}sqlite3_finalize(selectStatement);}}return saveSuccess;}