NSMutableDictionary 使用 key 在 Plist 中设置数据

Question

我有以下代码，

    for (int j= 0; j<data.count; j++){
        NSString *thedata = [data objectAtIndex:j];
        NSMutableDictionary * booksList = [NSMutableDictionary dictionary];
        if(j==0){
            [booksList setValue:[NSString stringWithFormat:@"%@",thedata]  forKey:@"name"];

        }
        if(j==1){
            [booksList setValue:[NSString stringWithFormat:@"%@",thedata]  forKey:@"author"];

        }

        [plistDict setObject:booksList forKey:@"Categories"];
     [plistDict writeToFile:pListPath atomically: YES];
    }

该代码假设将 booksList 保存到 plist 中称为类别的键中。这里发生的情况是，关键类别被清空，就好像我正在向其写入 null 一样。我已经记录了 booksList它返回了，

> 2011-08-27 14:22:15.821 SparkLibrary[8306:13403] {
    name = "\"dark matter\"";
}
2011-08-27 14:22:15.823 SparkLibrary[8306:13403] {
    author = "\"tamer ibrahim\"";
}
2011-08-27 14:22:15.824 SparkLibrary[8306:13403] {
}
2011-08-27 14:22:15.825 SparkLibrary[8306:13403] {
}
2011-08-27 14:22:15.826 SparkLibrary[8306:13403] {
}
2011-08-27 14:22:16.915 SparkLibrary[8306:13403] {
    name = "\"crypt tales\"";
}
2011-08-27 14:22:16.917 SparkLibrary[8306:13403] {
    author = "\"tamer ibrahim\"";
}
2011-08-27 14:22:16.918 SparkLibrary[8306:13403] {
}
2011-08-27 14:22:16.919 SparkLibrary[8306:13403] {
}
2011-08-27 14:22:16.920 SparkLibrary[8306:13403] {
}

那么有什么错误有人可以帮忙吗？

Answer 1

您正在为循环的每次迭代重新创建一个空白字典。移至

NSMutableDictionary * booksList = [NSMutableDictionary dictionary];

for 语句开始之前。而且，如果我理解正确，请将 write 和 setobject 移至循环结束之后。