我有一个图片幻灯片应用程序,它允许用户对 3 张图片进行评分。评分存储在名为 rated
的 NSMutableArray
中,如下所示:
2014-01-06 07:10:23.040 SlideShowSurvey[50425:70b] (
1, <-- Rating for Picture 1
2, <-- Rating for Picture 2
3 <-- Rating for Picture 3
)
然后使用以下代码将其保存到 .csv 文件中:
-(void)saveRatings
{
NSString *picRatings = [NSString stringWithFormat:@"%@, \n",self.rated];
// Find documents directory
NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *survey = [docPath stringByAppendingPathComponent:@"pictureRatings.csv"];
// Create new file if none exists
if (![[NSFileManager defaultManager] fileExistsAtPath:survey])
{
[[NSFileManager defaultManager] createFileAtPath:survey contents:nil attributes:nil];
}
NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:survey];
[fileHandle seekToEndOfFile];
[fileHandle writeData:[picRatings dataUsingEncoding:NSUTF8StringEncoding]];
[fileHandle closeFile];
}
然后我可以将 .csv 文件的结果显示到 UITextView,尽管它会准确显示数组的结构。例如,多个结果显示为:
(
1,
2,
3
),
(
1,
2,
3
),
(
1,
2,
3
)
有没有一种方法可以格式化数组以便将其保存为 1,2,3?我可以添加像图 1、图 2、图 3 这样的列标题吗?例如,我想在 UITextView 上显示如下结果:
Picture 1, Picture 2, Picture 3
1,2,3
1,2,3
1,2,3
我试过搜索,但似乎找不到这个答案。任何帮助表示赞赏!谢谢。
编辑:感谢 jrturton 的解决方案,我使用以下代码解决了这个问题:
// Set column titles for .csv
NSArray *columnTitleArray = @[@"Picture 1", @"Picture 2", @"Picture 3"];
NSString *columnTitle = [columnTitleArray componentsJoinedByString:@","];
NSString *columnTitleToWrite = [columnTitle stringByAppendingString:@"\n"];
// Separate ratings into cells
NSString *picRatings = [rated componentsJoinedByString:@","];
NSString *picRatingsToWrite = [picRatings stringByAppendingString:@"\n"];
// Find documents directory
..
然后将此添加到方法中以确保仅在创建新文件时设置列标题:
// Create new file if none exists
if (![[NSFileManager defaultManager] fileExistsAtPath:survey])
{
[[NSFileManager defaultManager] createFileAtPath:survey contents:nil attributes:nil];
// Set title for new file
NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:survey];
[fileHandle writeData:[columnTitleToWrite dataUsingEncoding:NSUTF8StringEncoding]];
}
..
最佳答案
这里有一个更简单的方法:
NSMutableString *csv = [NSMutableString string];
NSString *label = ...;
[csv appendFormat:@"%@,\n", label];
NSNumber *keyNum = ...;
[csv appendFormat:@"%d,%d\n", [keyNum intValue], [countNum intValue]];
NSString *filename = @"counts.csv";
NSError *error;
[csv writeToFile:filename atomically:YES encoding:NSUTF8StringEncoding error:&error];
关于ios - .csv 文件的 NSMutableArray 的格式内容,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/20945062/