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  • List转DataTable(反射) ; 将泛型集合类转换成DataTable ; 将集合类转换成DataTable

    public class ConvertX
        {
            #region 将集合类转换成DataTable
    
            /// <summary>
            /// 将集合类转换成DataTable
            /// </summary>
            /// <param name="list">集合</param>
            /// <returns></returns>
            public static System.Data.DataTable ToDataTable(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;
            }
    
            #endregion
    
    
            #region 将泛型集合类转换成DataTable
    
            /// <summary>
            /// 将泛型集合类转换成DataTable
            /// </summary>
            /// <typeparam name="T">集合项类型</typeparam>
            /// <param name="list">集合</param>
            /// <returns>数据集(表)</returns>
            public static DataTable ToDataTable<T>(IList<T> list)
            {
                return ToDataTable<T>(list, null);
            }
    
            /// <summary>
            /// 将泛型集合类转换成DataTable
            /// </summary>
            /// <typeparam name="T">集合项类型</typeparam>
            /// <param name="list">集合</param>
            /// <param name="propertyName">要返回的列的列名(比如你的表格里面有Name和其他列名,但是这里只写了Name就只返回Name这一列的所有数据)</param>
            /// <returns>数据集(表)</returns>
            public static DataTable ToDataTable<T>(IList<T> list, params string[] propertyName)
            {
                List<string> propertyNameList = new List<string>();
                if (propertyName != null)
                    propertyNameList.AddRange(propertyName);
    
                DataTable result = new DataTable();
                if (list.Count > 0)
                {
                    PropertyInfo[] propertys = list[0].GetType().GetProperties();
                    foreach (PropertyInfo pi in propertys)
                    {
                        if (propertyNameList.Count == 0)
                        {
                            result.Columns.Add(pi.Name, pi.PropertyType);
                        }
                        else
                        {
                            if (propertyNameList.Contains(pi.Name))
                                result.Columns.Add(pi.Name, pi.PropertyType);
                        }
                    }
    
                    for (int i = 0; i < list.Count; i++)
                    {
                        ArrayList tempList = new ArrayList();
                        foreach (PropertyInfo pi in propertys)
                        {
                            if (propertyNameList.Count == 0)
                            {
                                object obj = pi.GetValue(list[i], null);
                                tempList.Add(obj);
                            }
                            else
                            {
                                if (propertyNameList.Contains(pi.Name))
                                {
                                    object obj = pi.GetValue(list[i], null);
                                    tempList.Add(obj);
                                }
                            }
                        }
                        object[] array = tempList.ToArray();
                        result.LoadDataRow(array, true);
                    }
                }
                return result;
            }
    
            #endregion
        }


    实际调用方式

    1:返回所有的列

    DataTable dt = ConvertX.ToDataTable<PersonInfo>(list);
    image

    2:返回部分的列,这个后面的参数是指: 要返回的列的列名(比如你的集合里面有Name和其他列名,但是这里只写了Name就只返回Name这一列的所有数据

    DataTable dt = ConvertX.ToDataTable<PersonInfo>(list, "Name");
    image

    这个看在自己的类库里面  例如  Common层的 ConvertX 类,专门用于什么转换之类的

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  • 原文地址:https://www.cnblogs.com/joeylee/p/3863761.html
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