• 反射List<M> To DataTable|反射IList To DataTable|反射 DataTable To List<M>


     将DataTable集合反射获取 List<M>

     /// <summary>
            /// 根据DataTable集合反射获取 List<M>
            /// </summary>
            /// <typeparam name="M">泛型实体</typeparam>
            /// <param name="dt">DataTable</param>
            /// <returns>实体集合</returns>
            private static List<M> SetValueRow<M>(DataTable dt) where M : new()
            {
                List<M> list = new List<M>();
    
                Type type;
                PropertyInfo p;
                M m;
    
                foreach (DataRow row in dt.Rows)
                {
                    m = new M();
                    type = m.GetType();
    
                    foreach (DataColumn col in dt.Columns)
                    {
                        //获取一个字段的属性
                        p = type.GetProperty(col.ColumnName);
    
                        //实体中无对应属性
                        if (p == null)
                            continue;
    
                        string colDbType = row[col.ColumnName].GetType().FullName;
    
                        //结果集单元格中的值不为空时才赋值
                        if (colDbType != "System.DBNull")
                        {
                            switch (p.PropertyType.FullName)
                            {
                                case "System.Int64"://根据不同数据库数据类型作转换,如oracle的number(2)应转换为Int32,而不是默认的Decemal 
                                    p.SetValue(m, Convert.ToInt64(row[col.ColumnName]), null);
                                    break;
    
                                case "System.Int32":
                                    p.SetValue(m, Convert.ToInt32(row[col.ColumnName]), null);
                                    break;
    
                                case "System.Int16":
                                    p.SetValue(m, Convert.ToInt16(row[col.ColumnName]), null);
                                    break;
    
                                case "System.String":
                                    p.SetValue(m, Convert.ToString(row[col.ColumnName]), null);
                                    break;
    
                                case "System.Decimal":
                                    p.SetValue(m, Convert.ToDecimal(row[col.ColumnName]), null);
                                    break;
    
                                case "System.DateTime":
                                    p.SetValue(m, row[col.ColumnName], null);
                                    break;
    
                                case "System.Double":
                                    p.SetValue(m, Convert.ToDouble(row[col.ColumnName]), null);
                                    break;
    
                                case "System.Boolean":
                                    p.SetValue(m, Convert.ToBoolean(row[col.ColumnName]), null);
                                    break;
    
                                case "System.Byte":
                                    p.SetValue(m, Convert.ToByte(row[col.ColumnName]), null);
                                    break;
    
                                default:
                                    p.SetValue(m, row[col.ColumnName], null);
                                    break;
                            }
                        }
                    }
    
                    list.Add(m);
                }
    
                return list;
            }
            
    View Code

     将IList集合类转换成DataTable  

    /// <summary>  
            /// 将IList集合类转换成DataTable  
            /// </summary>  
            /// <param name="list">集合</param>  
            /// <returns></returns>  
            public static DataTable IListToDataTable(IList list)
            {
                DataTable result = new DataTable();
                if (list.Count > 0)
                {
                    PropertyInfo[] propertys = list[0].GetType().GetProperties();
                    foreach (PropertyInfo pi in propertys)
                    {
                        result.Columns.Add(pi.Name, pi.PropertyType);
                    }
    
                    for (int i = 0; i < list.Count; i++)
                    {
                        ArrayList tempList = new ArrayList();
                        foreach (PropertyInfo pi in propertys)
                        {
                            object obj = pi.GetValue(list[i], null);
                            tempList.Add(obj);
                        }
                        object[] array = tempList.ToArray();
                        result.LoadDataRow(array, true);
                    }
                }
                return result;
            }
    View Code
    将List<M>集合类转换成DataTable 
            /// <summary>  
            /// 将List<M>集合类转换成DataTable  
            /// </summary>  
            /// <param name="list">集合</param>  
            /// <returns></returns>  
            public static DataTable IListToDataTable<M>(List<M> list)
            {
                DataTable result = new DataTable();
                if (list.Count > 0)
                {
                    PropertyInfo[] propertys = list[0].GetType().GetProperties();
                    foreach (PropertyInfo pi in propertys)
                    {
                        result.Columns.Add(pi.Name, pi.PropertyType);
                    }
    
                    for (int i = 0; i < list.Count; i++)
                    {
                        ArrayList tempList = new ArrayList();
                        foreach (PropertyInfo pi in propertys)
                        {
                            object obj = pi.GetValue(list[i], null);
                            tempList.Add(obj);
                        }
                        object[] array = tempList.ToArray();
                        result.LoadDataRow(array, true);
                    }
                }
                return result;
            }
    View Code

    全局静态类 泛型方法
    /// <summary>
    /// 全局静态类
    /// </summary>
    public static class GlobalStaticClass : Object
    {
    
        public static List<M> ToModelList<M>(this object obj) where M : new()
        {
            List<M> list = new List<M>();
    
            Type type;
            PropertyInfo p;
            M m;
            DataTable dt = (DataTable)obj;
    
            foreach (DataRow row in dt.Rows)
            {
                m = new M();
                type = m.GetType();
    
                foreach (DataColumn col in dt.Columns)
                {
                    //获取一个字段的属性
                    p = type.GetProperty(col.ColumnName);
    
                    //实体中无对应属性
                    if (p == null)
                        continue;
    
                    string colDbType = row[col.ColumnName].GetType().FullName;
    
                    //结果集单元格中的值不为空时才赋值
                    if (colDbType != "System.DBNull")
                    {
                        switch (p.PropertyType.FullName)
                        {
                            case "System.Int64"://根据不同数据库数据类型作转换,如oracle的number(2)应转换为Int32,而不是默认的Decemal 
                                p.SetValue(m, Convert.ToInt64(row[col.ColumnName]), null);
                                break;
    
                            case "System.Int32":
                                p.SetValue(m, Convert.ToInt32(row[col.ColumnName]), null);
                                break;
    
                            case "System.Int16":
                                p.SetValue(m, Convert.ToInt16(row[col.ColumnName]), null);
                                break;
    
                            case "System.String":
                                p.SetValue(m, Convert.ToString(row[col.ColumnName]), null);
                                break;
    
                            case "System.Decimal":
                                p.SetValue(m, Convert.ToDecimal(row[col.ColumnName]), null);
                                break;
    
                            case "System.DateTime":
                                p.SetValue(m, row[col.ColumnName], null);
                                break;
    
                            case "System.Double":
                                p.SetValue(m, Convert.ToDouble(row[col.ColumnName]), null);
                                break;
    
                            case "System.Boolean":
                                p.SetValue(m, Convert.ToBoolean(row[col.ColumnName]), null);
                                break;
    
                            case "System.Byte":
                                p.SetValue(m, Convert.ToByte(row[col.ColumnName]), null);
                                break;
    
                            default:
                                p.SetValue(m, row[col.ColumnName], null);
                                break;
                        }
                    }
                }
    
                list.Add(m);
            }
    
            return list;
        }
    
    }
    View Code

    实体父类,实体继承此类后,实体对象可调用this.SetValue(object) 方法通过反射给自身对象赋值

        public class ModelBase
        {
            protected bool isNull = true;
            public bool IsNull
            {
                get { return isNull; }
                set { isNull = value; }
            }
            protected void SetValue(object info)
            {
                foreach (FieldInfo fi in info.GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Instance))
                {
                    this.GetType().GetField(fi.Name, BindingFlags.NonPublic | BindingFlags.Instance).SetValue(this, fi.GetValue(info));
                }
            }
            public void SetValue(SqlDataReader dr)
            {
                if (dr.Read())
                {
                    foreach (FieldInfo fi in this.GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Instance))
                    {
                        if (fi.Name != "isNull")
                        {
                            object rel = dr[fi.Name];
                            if (dr[fi.Name] != Convert.DBNull)
                            {
                                fi.SetValue(this, dr[fi.Name]);
                            }
    
                        }
                    }
                    this.isNull = false;
                }
                dr.Close();
            }
            public void SetValue(DataRow dr)
            {
                foreach (FieldInfo fi in this.GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Instance))
                {
                    if (fi.Name != "isNull")
                    {
                        if (dr.Table.Columns.Contains(fi.Name))
                        {
                            object rel = dr[fi.Name];
                            if (dr[fi.Name] != Convert.DBNull)
                            {
                                fi.SetValue(this, dr[fi.Name]);
                            }
                        }
                    }
                }
                this.isNull = false;
    
            }
    
    
    
        }
    View Code



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  • 原文地址:https://www.cnblogs.com/yonsy/p/2654814.html
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