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我正在使用泛型来执行一些基本的插入/更新/使用linq2sql从数据库中进行选择。Linq2sql泛型按列和值选择
我有以下和即时通讯尝试将其转换为需要列名和对象值来选择基于关闭,但我不能让它的工作。
public static T SelectByID<T>(string id) where T : class
{
try
{
using (DataContext db = new DataContext(CHCGlobal.ConnectionString))
{
//get Table of type T
var table = db.GetTable<T>();
//get object mappings
MetaModel modelMap = table.Context.Mapping;
//get the data members for this type
ReadOnlyCollection<MetaDataMember> dataMembers = modelMap.GetMetaType(typeof(T)).DataMembers;
//find primary key
string pk = (dataMembers.Single<MetaDataMember>(m => m.IsPrimaryKey)).Name;
//return a single object with the id matching the pk field
return table.SingleOrDefault<T>(delegate (T t)
{
string memberId = t.GetType().GetProperty(pk).GetValue(t, null).ToString();
return memberId.ToString() == id.ToString();
});
}
}
catch (Exception)
{
throw;
}
}
这是函数即时尝试创建,但即时堵塞在选择语句。
public static List<T> SelectByKeyValue<T>(string id, object value) where T : class
{
try
{
using (DataContext db = new DataContext(CHCGlobal.ConnectionString))
{
//get Table of type T
var table = db.GetTable<T>();
//get object mappings
MetaModel modelMap = table.Context.Mapping;
//get the data members for this type
ReadOnlyCollection<MetaDataMember> dataMembers = modelMap.GetMetaType(typeof(T)).DataMembers;
//find key
string pk = (dataMembers.Single<MetaDataMember>(m => m.Name.Equals(id))).Name;
//NOT WORKING
return table.Select<T, T>(delegate (T t)
{
var memberID = t.GetType().GetProperty(pk).GetValue(t, null);
return memberID.Equals(value);
}).ToList<T>();
}
}
catch (Exception)
{
throw;
}
}
我已更改我的代码以匹配上面。但现在我得到一个异常说明:方法'System.Reflection.PropertyInfo GetProperty(System.String)'没有支持转换为SQL –