保存在一个文件中的NSMutableArray所有内容的iOS

Question

我的SQLite数据库，并与查询导出一些结果

sqlite3 *MyDB; 
const char *dbpath = [StringPathDB UTF8String]; // Convert NSString to UTF-8 
NSString *querySQL = @"select * from chat order by id desc limit 20"; 



if (sqlite3_open(dbpath, &MyDB) == SQLITE_OK) 
{ 

    const char *sql = [querySQL UTF8String]; 

    sqlite3_stmt *searchStatement; 

    if (sqlite3_prepare_v2(MyDB, sql, -1, &searchStatement, NULL) == SQLITE_OK) 
    { 
     while (sqlite3_step(searchStatement) == SQLITE_ROW) 
     { 
      NSString *nickname = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 0)]; 
      NSString *time = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 1)]; 
      NSString *text = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 2)]; 

然后我把所有的NSMutableArray

NSMutableArray *list = [[NSMutableArray alloc] init]; 

[list addObject:nickname]; 
[list addObject:time]; 
[list addObject:text]; 

当我试图挽救人的文件与此代码

for(int i = 0; i < [list count]; i++) { 

        NSLog(@"%@",list); 
        [list writeToFile:filePATH atomically:YES]; 
        break; 
       } 

它在NSLog中正确邮戳，但在文件只保存最后一个记录不是所有阵列年。 请帮帮我！

Answer 1

您需要创建一次NSMutableArray并对其进行全部添加。

NSMutableArray *list = [[NSMutableArray alloc] init]; 
while (sqlite3_step(searchStatement) == SQLITE_ROW) 
{ 
    NSString *nickname = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 0)]; 
    NSString *time = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 1)]; 
    NSString *text = [NSString stringWithUTF8String:(char *)sqlite3_column_text(searchStatement, 2)]; 
    [list addObject:nickname]; 
    [list addObject:time]; 
    [list addObject:text]; 
    ... 
} 
[list writeToFile:filePATH atomically:YES];