如何在循环中将NSDictionary的值存储到NSMutableArray？

Question

我正在从数据库中获取数据，并且我将获得数据库中最后的相同数据。 如何在nsmutable数组中存储字典值。

这是我的代码！

  - (NSDictionary *) getPreparedAllRow
 {

NSMutableDictionary *dRow=[[NSMutableDictionary alloc]init];
NSMutableArray *data=[[NSMutableArray alloc]init];

int counter=0;
while(sqlite3_step(statment) == SQLITE_ROW)
{
    int Column_Count = sqlite3_column_count(statment);
    if(Column_Count >= 1)
    {

        for(int count =0 ; count < Column_Count ; count++)
        {
            [dRow setObject:[self columnValue:count] forKey:@(sqlite3_column_name(statment, count))];
            //dRow [ @(sqlite3_column_name(statment, count))] = [self columnValue:count];
        }
    }
    NSLog(@"%@",dRow);
    [data insertObject:dRow atIndex:counter];
    counter++;
    NSLog(@"%@",data);
}
NSLog(@"%@",data);
return dRow;
 }

当计数所有数据记录时9个计数器变量。 并且所有数据都被最后一个数据覆盖。

这是我的日志。

 (
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
     "Id" = 1;
    "Name" = Priyank;
},
    {
    "Id" = 1;
    "Name" = Priyank;
}

）

Answer 1

实际上，返回类型应该是数组，并且不需要计数器变量，请尝试以下操作：

- (NSArray *)getPreparedAllRow
 {


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

while(sqlite3_step(statment) == SQLITE_ROW)
{
    NSMutableDictionary *dRow=[[NSMutableDictionary alloc]init];
    int Column_Count = sqlite3_column_count(statment);
    if(Column_Count >= 1)
    {

        for(int count =0 ; count < Column_Count ; count++)
        {
            [dRow setObject:[self columnValue:count] forKey:@(sqlite3_column_name(statment, count))];
            //dRow [ @(sqlite3_column_name(statment, count))] = [self columnValue:count];
        }
    }
    NSLog(@"%@",dRow);
    [data addObject:dRow];
    NSLog(@"%@",data);
}
NSLog(@"%@",data);
return data;
 }

Answer 2

您需要在每次迭代中创建一个新的NSMutableDictionary * dRow：

- (NSDictionary *) getPreparedAllRow
 {

//NSMutableDictionary *dRow=[[NSMutableDictionary alloc]init];
NSMutableArray *data=[[NSMutableArray alloc]init];

int counter=0;
while(sqlite3_step(statment) == SQLITE_ROW)
{
    int Column_Count = sqlite3_column_count(statment);

    NSMutableDictionary *dRow=[[NSMutableDictionary alloc]init];

    if(Column_Count >= 1)
    {

        for(int count =0 ; count < Column_Count ; count++)
        {
            [dRow setObject:[self columnValue:count] forKey:@(sqlite3_column_name(statment, count))];
            //dRow [ @(sqlite3_column_name(statment, count))] = [self columnValue:count];
        }
    }
    NSLog(@"%@",dRow);
    [data insertObject:dRow atIndex:counter];
    counter++;
    NSLog(@"%@",data);
}
NSLog(@"%@",data);
return dRow;
 }

而且我认为您想返回NSMutableArray * ?? 也许那里也有错误...

Answer 3

如果您的NSDictionary中存储了一些值，请尝试使用此语句。 这将自动将特定的键值放入该数组。

arrayName = [dictionaryName valueForKey:@"keyName"];

或者你可以尝试一下

[arrayName addObject:[dictionaryName objectForKey:@"keyName"];

Answer 4

首先全部创建一个名为的NSObject类

/ ** #import“ StudentDTO.h” **** /

 @interface StudentDTO : NSObject
    {
        int ID;
        NSString *stu_name;
    }
    @property (nonatomic, readwrite) int ID;
    @property (nonatomic, retain) NSString *stu_name;

@end

/ ** #import“ StudentDTO.m” **** /

@implementation StudentDTO

@synthesize ID,stu_name;

@end

////现在在您的代码中导入#import“ StudentDTO.h”

-(NSDictionary *) getPreparedAllRow

 {

NSMutableDictionary *dRow=[[NSMutableDictionary alloc]init];
NSMutableArray *data=[[NSMutableArray alloc]init];
int counter=0;
while(sqlite3_step(statment) == SQLITE_ROW)
{
   int Column_Count = sqlite3_column_count(statment);
    if(Column_Count >= 1)
    {

        for(int count =0 ; count < Column_Count ; count++)
        {
            [dRow setObject:[self columnValue:count] forKey:@(sqlite3_column_name(statment, count))];
            //dRow [ @(sqlite3_column_name(statment, count))] = [self columnValue:count];
        }
    }
    NSLog(@"%@",dRow);
    StudentDTO *studto=[[StudentDTO alloc]init];
    studto.ID=[dRow objectforkey:@"Id"];
    studto.stu_name=[dRow objectforkey:@"Name"];[data addobject:studto];
    counter++;
    NSLog(@"%@",data);}NSLog(@"%@",data);return dRow;

 }