Question

过去一周我一直在讨论这个问题，并且无法弄清楚如何解决这个问题。

我目前有一个应用程序，它接收调查数据，以 surveydata -mm-dd-yyyy的形式将其保存为csv文件。这通常发生在持续多天的事件中，因此正常事件周末将是

surveydata -09-13-2014 surveydata -09-14-2014 surveydata -09-15-2014

现在我希望参加这些活动的人能够简单地点击一个按钮，该按钮将在电子邮件前面添加所有那些存储在apps文档文件夹中的文件。

我拥有相当多的设置和功能减去能够告诉应用程序查找具有这些名称的文件并将它们包含在电子邮件中。

这是我的代码

- (IBAction)emailButton:(id)sender {

    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"MM-dd-yyyy"];

    NSString *dateString = [dateFormat stringFromDate:[NSDate date]];
    NSString *path = [[self applicationDocumentsDirectory].path
                      stringByAppendingPathComponent:[NSString stringWithFormat:@"_SurveyData_%@.csv",dateString]];

  /*  if(![[NSFileManager defaultManager] fileExistsAtPath:path]) {*/
        MFMailComposeViewController *mailer = [[MFMailComposeViewController alloc] init];
        mailer.mailComposeDelegate = self;
        [mailer setSubject:@"CSV File"];
        [mailer setToRecipients:toRecipents];
        [mailer addAttachmentData:[NSData dataWithContentsOfFile:@"_SurveyData_%@.csv"]
                         mimeType:@"text/csv"
                         fileName:@"FileName"];
        [self presentModalViewController:mailer animated:YES];

    //}

}

如果有人能帮助我，因为我觉得我很近，我只是等待所有点击并有意义。

如果我遗漏了某些内容或我的代码太模糊，请告诉我。

这是我用来将数据写入CSV的代码，以便更好地了解它的全部内容。

-(void)writeSurveyDataToCSV:(NSString *)text {
    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"MM-dd-yyyy"];

    NSString *dateString = [dateFormat stringFromDate:[NSDate date]];
    NSString *path = [[self applicationDocumentsDirectory].path
                      stringByAppendingPathComponent:[NSString stringWithFormat:@"_SurveyData_%@.csv",dateString]];
    if(![[NSFileManager defaultManager] fileExistsAtPath:path]) {

        NSString *header = @" gender,age,zip code,duration(sec), own a bike?,response1,response2,response3,response4,response5,response6, response7, response8, response9\n";
        [header writeToFile:path atomically:YES
                 encoding:NSUTF8StringEncoding error:nil];

    }
    text = [text stringByAppendingString:@"\n"];
    NSFileHandle *fileHandle = [NSFileHandle fileHandleForWritingAtPath:path];
    [fileHandle seekToEndOfFile];
    [fileHandle writeData:[text dataUsingEncoding:NSUTF8StringEncoding]];

}

编辑：感谢Danh的指导，这是我的解决方案

- (IBAction)emailButton:(id)sender {

    NSArray *toRecipents = [NSArray arrayWithObject:@"reflex@ilovetheory.com"];

    MFMailComposeViewController *mailer = [[MFMailComposeViewController alloc] init];
    mailer.mailComposeDelegate = self;
    [mailer setSubject:@"CSV File"];
    [mailer setToRecipients:toRecipents];

    NSArray *filenames = [self filesNamesStartingAt:[NSDate date] count:165];
    [self attachFilesNamed:filenames toMailer:mailer];

    [self presentModalViewController:mailer animated:YES];

}

// answer count strings, named for days starting at date and the count-1 following days
- (NSArray *)filesNamesStartingAt:(NSDate *)date count:(NSInteger)count {

    NSMutableArray *result = [NSMutableArray array];
    static NSDateFormatter *dateFormat;

    if (!dateFormat) {
        dateFormat = [[NSDateFormatter alloc] init];
        [dateFormat setDateFormat:@"MM-dd-yyyy"];
    }

    for (int i=0; i<count; ++i) {
        NSString *dateString = [dateFormat stringFromDate:date];
        NSString *path = [[self applicationDocumentsDirectory].path
                          stringByAppendingPathComponent:[NSString stringWithFormat:@"_SurveyData_%@.csv",dateString]];
        [result addObject:path];
        date = [self addDayToDate:date];
    }
    for (int i=0; i<count; ++i) {
        NSString *dateString = [dateFormat stringFromDate:date];
        NSString *path = [[self applicationDocumentsDirectory].path
                          stringByAppendingPathComponent:[NSString stringWithFormat:@"_SurveyData_%@.csv",dateString]];
        [result addObject:path];
        date = [self subDayToDate:date];
    }
    return result;
}

// answer a new date, advanced one day from the passed date
- (NSDate *)addDayToDate:(NSDate *)date {

    NSDateComponents *components = [[NSDateComponents alloc] init];
    [components setDay:1];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

    return [gregorian dateByAddingComponents:components toDate:date options:0];
}

- (NSDate *)subDayToDate:(NSDate *)date {

    NSDateComponents *components = [[NSDateComponents alloc] init];
    [components setDay:-1];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

    return [gregorian dateByAddingComponents:components toDate:date options:0];
}

- (void)attachFilesNamed:(NSArray *)paths toMailer:(MFMailComposeViewController *)mailer {

    for (NSString *path in paths) {
        if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
            NSData *data = [NSData dataWithContentsOfFile:path];
            [mailer addAttachmentData:data mimeType:@"text/csv" fileName:path];
        } else {
            NSLog(@"warning, no file at path %@", path);
        }
    }
}

- (NSURL *)applicationDocumentsDirectory {
    return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory
                                                   inDomains:NSUserDomainMask] lastObject];
}

Answer 1

你正在创建一个文件路径，但是在[mailer addAttachmentData]调用中，你并没有像我想象的那样传递那条路径 - 相反它只是得到了你的字符串用于构建路径，因此您的NSData将是零，因为它不是磁盘上任何内容的完整路径。尝试将该行更改为[mailer addAttachmentData:[NSData dataWithContentsOfFile:path]]

Answer 2

看起来你看起来非常接近。也许需要更多地解决问题：

从一个方法开始，该方法将在给定的一天开始创建几天的文件名...

// answer count strings, named for days starting at date and the count-1 following days
- (NSArray *)filesNamesStartingAt:(NSDate *)date count:(NSInteger)count {

    NSMutableArray *result = [NSMutableArray array];
    static NSDateFormatter *dateFormat;

    if (!dateFormat) {
        dateFormat = [[NSDateFormatter alloc] init];
        [dateFormat setDateFormat:@"MM-dd-yyyy"];
    }

    for (int i=0; i<count; ++i) {
        NSString *dateString = [dateFormat stringFromDate:date];
        NSString *path = [[self applicationDocumentsDirectory].path
                      stringByAppendingPathComponent:[NSString stringWithFormat:@"_SurveyData_%@.csv",dateString]];
        [result addObject:path];
        date = [self addDayToDate:date];
    }
    return result;
}

// answer a new date, advanced one day from the passed date
- (NSDate *)addDayToDate:(NSDate *)date {

    NSDateComponents *components = [[NSDateComponents alloc] init];
    [components setDay:1];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

    return [gregorian dateByAddingComponents:components toDate:date options:0];
}

现在，添加一个将一组命名文件附加到邮件控制器的方法：

- (void)attachFilesNamed:(NSArray *)paths toMailer:(MFMailComposeViewController *)mailer {
    for (NSString *path in paths) {
        if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
            NSData *data = [NSData dataWithContentsOfFile:path];
            [mailer addAttachmentData:data mimeType:@"text/csv" fileName:path];
        } else {
            NSLog(@"warning, no file at path %@", path);
        }
    }
}

其余的几乎写出来（我希望）......

MFMailComposeViewController *mailer = [[MFMailComposeViewController alloc] init];
mailer.mailComposeDelegate = self;
[mailer setSubject:@"CSV File"];
[mailer setToRecipients:toRecipents];

NSArray *filenames = [self fileNamesStartingAt:[NSDate date] count:3];
[self attachFilesNamed:filenames toMailer:mailer];

请注意，正如所写，这将使用今天和接下来的两天文件名。如果这不是您的要求，您可以调整addDay方法以创建减法天数方法，然后使用串联方法。

通过电子邮件从我的应用程序发送多个递增的csv

2 个答案: