在循环中使用动态expandoobject建立列表，参考更新所有项目

Question

我试图通过

使用EF仅从表中提取某些列

dynamic var = new ExpandoObject.

最终目标是允许用户选择他们想要从API返回的字段，并使代码仅提取那些列。

我的问题是，假设根据他们的数据有100条记录，我的动态对象是一个引用，因此当我更新一个列表项时，它们都会被更新。

代码：

dynamic expando = new ExpandoObject();
var output = new List<ExpandoObject>();

PopulateDynamicObject(expando); // adds the columns the user had marked to include

static dynamic PopulateDynamicObject(dynamic rootObject)
{
    var fields = GetLeadFields();

    foreach (var field in fields)
    {
        AddProperty(rootObject, field.FieldName, "");
    }

    return rootObject;
}

// get data from database. snip

// List all fields possible but UpdateProperty will only update properties which exist, therefore it honours PopulateDynamicObject
UpdateProperty(expando, "LeadId", dbLead.leadID);
UpdateProperty(expando, "CompanyId", dbLead.companyID);
UpdateProperty(expando, "CompanyName", dbLead.company);
UpdateProperty(expando, "UnitIdentity", dbLead.unitIdentity);
UpdateProperty(expando, "BadgeId", dbLead.badgeID);
UpdateProperty(expando, "ScanDate", dbLead.scanDate);
UpdateProperty(expando, "FirstName", dbLead.firstName);
UpdateProperty(expando, "LastName", dbLead.lastName);
UpdateProperty(expando, "Company", dbLead.company);
UpdateProperty(expando, "Address1", dbLead.address1);
UpdateProperty(expando, "Address2", dbLead.address2);
UpdateProperty(expando, "Address3", dbLead.address3);

static void UpdateProperty(ExpandoObject expando, string propertyName, object propertyValue = null)
{
    var expandoDict = expando as IDictionary<string, object>;

    if (expandoDict.ContainsKey(propertyName))
        expandoDict[propertyName] = propertyValue;
}

但是最终结果是n行都具有相同的数据。