Question

从.NET类中提取单值的任何字段或属性的最佳方法是什么（即不是数组，集合等）

到目前为止我已经

了

[...]
FieldInfo[] fieldInfos = foo.GetType().GetFields(bindingFlags);
fieldInfos = fieldInfos.Where(f => !f.FieldType.IsArrayOrCollection()).ToArray();
[...]

这是在静态扩展类

中

public static bool IsArrayOrCollection(this Type testType)
{
    if (testType.IsArray)
        return true;
    if (testType is IEnumerable)
        return true;
    return false;
}

它有效，但我想知道是否有更好的方法？是否会有错过的角落案件？

这个的基本原理是我将单值成员存储在数据库表中作为键值对。显然，这对数组不起作用，因为值是嵌套类型，需要存储在自己的单独表中。

Answer 1

您可以使用以下扩展方法：

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        John Rhys Davis - (Gimli)
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那么您可以使用以下方法检索键值对：

public static class Extensions
{
    public static IDictionary<string, object> GetSimpleFieldValues(this object obj)
    {
        return obj.GetType()
            .GetFields(BindingFlags.Instance | BindingFlags.Public)
            .Where(f => f.FieldType.IsSimpleType())
            .ToDictionary(k => k.Name, v => v.GetValue(obj));
    }

    public static bool IsSimpleType(this Type type)
    {
        return type.IsValueType 
            || type.IsPrimitive 
            || new Type[] {
                    typeof(String),
                    typeof(Decimal),
                    typeof(DateTime),
                    typeof(DateTimeOffset),
                    typeof(TimeSpan),
                    typeof(Guid)
                }.Contains(type) 
            || Convert.GetTypeCode(type) != TypeCode.Object;
    }
}

基于this SO回答。

请注意，这将返回用户定义的IDictionary<string, object> values = new YourClass().GetSimpleFieldValues();的误报。

从C＃类中提取非数组/集合的所有字段

1 个答案: