在类文件的顶部,我增加一类:为什么我得到错误,该变量需要是静态的?
public class World
{
public List<Continent> continents;
public World()
{
continents = new List<Continent>();
}
}
public class Continent
{
public string name;
public List<Country> countries { get; set; }
public Continent()
{
name = string.Empty;
countries = new List<Country>();
}
}
public class Country
{
public string name { get; set; }
public List<string> imageUrls { get; set; }
public Country()
{
name = string.Empty;
imageUrls = new List<string>();
}
}
当Form1中使用它:
foreach (ExtractImages.Continent continent in ExtractImages.World.continents)
{
Console.WriteLine(continent.name);
foreach (ExtractImages.Country country in continent.countries)
{
Console.WriteLine(country.name);
foreach (string imageUri in country.imageUrls)
{
Console.WriteLine(imageUri);
}
}
}
我得到的错误在Form1上:
ExtractImages.World.continents
上线:
foreach (ExtractImages.Continent continent in ExtractImages.World.continents)
严重性代码说明项目文件的线路抑制状态 错误CS0120的对象引用需要非静态字段,方法或属性“ExtractImages.World.continents”
更新
第一在类文件中,我使用世界之前,它在form1中使用它: 当我在Form1中创建世界的新实例时,它将全部为空。
public void ImagesLinks()
{
try
{
int counter = 0;
foreach (string countryCode in countriescodes)
{
Country country = new Country();
country.name = countriesnames[counter];
List<string> imageUrl = new List<string>();
counter++;
for (int cnt = 0; cnt < DatesAndTimes.Count(); cnt++)
{
string imageUrlIrTrue = firstUrlPart + countryCode + secondUrlPart + DatesAndTimes[cnt] + thirdUrlPart + "true";
string imageUrlIrFalse = firstUrlPart + countryCode + secondUrlPart + DatesAndTimes[cnt] + thirdUrlPart + "false";
imageUrl.Add(imageUrlIrTrue);
imageUrl.Add(imageUrlIrFalse);
if (cnt == 9)
{
cnt = 0;
break;
}
}
country.imageUrls = imageUrl;
Europe.countries.Add(country);
}
world.continents.Add(Europe);
}
这是在Form1的现在:
ExtractImages.World world = new ExtractImages.World();
foreach (ExtractImages.Continent continent in world.continents)
{
Console.WriteLine(continent.name);
foreach (ExtractImages.Country country in continent.countries)
{
Console.WriteLine(country.name);
foreach (string imageUri in country.imageUrls)
{
Console.WriteLine(imageUri);
}
}
}
你像一个静态对象调用它时,它不是一成不变的。 – Abion47
因为您将它用作静态类。你不需要在类型的*实例*上使用'.continents'。 – Rob