c# - 如何检查 .NET 中存在的文化

Question

我有这段代码，当我尝试获取不存在的文化时，我会遇到异常。
是否存在类似TryGetCultureInfo返回bool值的方法？我不想使用try-catch声明

CultureInfo culture = CultureInfo.GetCultureInfo(cultureCode);
if (culture == null)
{
    culture = CultureInfo.GetCultureInfo(DefaultCultureCode);
}

Answer 1

您可以编写一个返回布尔值的 DoesCultureExist 方法，如下所示：

private static bool DoesCultureExist(string cultureName)
{
    return CultureInfo.GetCultures(CultureTypes.AllCultures).Any(culture => string.Equals(culture.Name, cultureName, StringComparison.CurrentCultureIgnoreCase));
}

Answer 2

我认为没有这样的方法。因此，您可以只try-catch检查或检查所有已安装的文化：

string cultureCode = "de-DE";
CultureInfo[] cultures = CultureInfo.GetCultures(CultureTypes.AllCultures & ~CultureTypes.NeutralCultures);
var culture = cultures.FirstOrDefault(c => c.Name.Equals(cultureCode, StringComparison.OrdinalIgnoreCase));
if (culture == null)
{
    culture = cultures.FirstOrDefault(c => c.Name.Equals(DefaultCultureCode, StringComparison.OrdinalIgnoreCase));
    if (culture == null)
        culture = CultureInfo.CurrentCulture;
}

但我更喜欢try-catch，我相信它更有效。

public bool TryGetCultureInfo(string cultureCode, string DefaultCultureCode, out CultureInfo culture)
{
    try
    {
        culture = CultureInfo.GetCultureInfo(cultureCode);
        return true;
    } catch(CultureNotFoundException)
    {
        if (DefaultCultureCode == null)
            culture = CultureInfo.CurrentCulture;
        else
        {
            try
            {
                culture = CultureInfo.GetCultureInfo(DefaultCultureCode);
            } catch (CultureNotFoundException)
            {
                culture = CultureInfo.CurrentCulture;
            }
        }
    }
    return false;
}

Answer 3

如果您希望它更快，您可以使用：

internal static class Culture
{
    private static readonly HashSet<string> CultureNames = CreateCultureNames();

    internal static bool Exists(string name)
    {
        return CultureNames.Contains(name);
    }

    private static HashSet<string> CreateCultureNames()
    {
        var cultureInfos = CultureInfo.GetCultures(CultureTypes.AllCultures)
                                      .Where(x => !string.IsNullOrEmpty(x.Name))
                                      .ToArray();
        var allNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        allNames.UnionWith(cultureInfos.Select(x => x.TwoLetterISOLanguageName));
        allNames.UnionWith(cultureInfos.Select(x => x.Name));
        return allNames;
    }
}

Answer 4

不，AFAIK 是不可能的。您可以先检查文化是否存在，在这种情况下获取它。

以下代码显示了如何执行此操作：

    private static CultureInfo GetCulture(string name)
    {
        if (!CultureExists(name)) return null;

        return CultureInfo.GetCultureInfo(name);
    }

    private static bool CultureExists(string name)
    {
        CultureInfo[] availableCultures =
            CultureInfo.GetCultures(CultureTypes.AllCultures);

        foreach (CultureInfo culture in availableCultures)
        {
            if (culture.Name.Equals(name))
                return true;
        }

        return false;
    }

希望能帮助到你