Conversion Between DataTable and List in C#

时间:2023-11-12 13:32:08

1.List to DataTable

 public static DataTable ToDataTable<TSource>(this IList<TSource> data)
{
DataTable dataTable = new DataTable(typeof(TSource).Name);
PropertyInfo[] props = typeof(TSource).GetProperties(BindingFlags.Public | BindingFlags.Instance);
foreach (PropertyInfo prop in props)
{
dataTable.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ??
prop.PropertyType);
} foreach (TSource item in data)
{
var values = new object[props.Length];
for (int i = 0; i < props.Length; i++)
{
values[i] = props[i].GetValue(item, null);
}
dataTable.Rows.Add(values);
}
return dataTable;
}

2.DataTable To List

public static List<TSource> ToList<TSource>(this DataTable dataTable) where TSource : new()
{
var dataList = new List<TSource>(); const BindingFlags flags = BindingFlags.Public | BindingFlags.Instance | BindingFlags.NonPublic;
var objFieldNames = (from PropertyInfo aProp in typeof(TSource).GetProperties(flags)
select new
{
Name = aProp.Name,
Type = Nullable.GetUnderlyingType(aProp.PropertyType) ??
aProp.PropertyType
}).ToList();
var dataTblFieldNames = (from DataColumn aHeader in dataTable.Columns
select new
{
Name = aHeader.ColumnName,
Type = aHeader.DataType
}).ToList();
var commonFields = objFieldNames.Intersect(dataTblFieldNames).ToList(); foreach (DataRow dataRow in dataTable.AsEnumerable().ToList())
{
var aTSource = new TSource();
foreach (var aField in commonFields)
{
PropertyInfo propertyInfos = aTSource.GetType().GetProperty(aField.Name);
var value = (dataRow[aField.Name] == DBNull.Value) ?
null : dataRow[aField.Name]; //if database field is nullable
propertyInfos.SetValue(aTSource, value, null);
}
dataList.Add(aTSource);
}
return dataList;
}