Comment puis-je convertir un DataTable dans une Dynamique d'objet?

Comment sur avec DynamicObject:

public static class DataTableX
{
    public static IEnumerable<dynamic> AsDynamicEnumerable(this DataTable table)
    {
        //Validate argument here..

        return table.AsEnumerable().Select(row => new DynamicRow(row));
    }

    private sealed class DynamicRow : DynamicObject
    {
        private readonly DataRow _row;

        internal DynamicRow(DataRow row) { _row = row; }

        //Interprets a member-access as an indexer-access on the 
        //contained DataRow.
        public override bool TryGetMember(GetMemberBinder binder, out object result)
        {
            var retVal = _row.Table.Columns.Contains(binder.Name);
            result = retVal ? _row[binder.Name] : null;
            return retVal;
        }
    }
}

Vous pouvez également essayer primordial TrySetMember si vous souhaitez faire de la dynamique-ligne de l'écriture.

Utilisation:

  DataTable table = ...
  var dynamicTable = table.AsDynamicEnumerable();

  var firstRowsNameField = dynamicTable.First().Name;

OriginalL'auteur Ani

Précédente suneelsarraf codes générés seulement exécution dynamique de l'objet de la propriété en tant que chaîne de caractères.
mise à jour suivante va générer chaque propriété basée sur la DataTable colonne du type de données.

public static class DataTableExtension
{
///<summary>
/// Convert a database data table to a runtime dynamic definied type collection (dynamic class' name as table name).
///</summary>
///<param name="dt"></param>
///<param name="className"></param>
///<returns></returns>
public static List<dynamic> ToDynamicList(DataTable dt, string className)
{
return ToDynamicList(ToDictionary(dt), getNewObject(dt.Columns, className));
}
private static List<Dictionary<string, object>> ToDictionary(DataTable dt)
{
var columns = dt.Columns.Cast<DataColumn>();
var Temp = dt.AsEnumerable().Select(dataRow => columns.Select(column =>
new { Column = column.ColumnName, Value = dataRow[column] })
.ToDictionary(data => data.Column, data => data.Value)).ToList();
return Temp.ToList();
}
private static List<dynamic> ToDynamicList(List<Dictionary<string, object>> list, Type TypeObj)
{
dynamic temp = new List<dynamic>();
foreach (Dictionary<string, object> step in list)
{
object Obj = Activator.CreateInstance(TypeObj);
PropertyInfo[] properties = Obj.GetType().GetProperties();
Dictionary<string, object> DictList = (Dictionary<string, object>)step;
foreach (KeyValuePair<string, object> keyValuePair in DictList)
{
foreach (PropertyInfo property in properties)
{
if (property.Name == keyValuePair.Key)
{
if (keyValuePair.Value != null && keyValuePair.Value.GetType() != typeof(System.DBNull))
{
if (keyValuePair.Value.GetType() == typeof(System.Guid))
{
property.SetValue(Obj, keyValuePair.Value, null);
}
else
{
property.SetValue(Obj, keyValuePair.Value, null);
}
}
break;
}
}
}
temp.Add(Obj);
}
return temp;
}
private static Type getNewObject(DataColumnCollection columns, string className)
{
AssemblyName assemblyName = new AssemblyName();
assemblyName.Name = "YourAssembly";
System.Reflection.Emit.AssemblyBuilder assemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.Run);
ModuleBuilder module = assemblyBuilder.DefineDynamicModule("YourDynamicModule");
TypeBuilder typeBuilder = module.DefineType(className, TypeAttributes.Public);
foreach (DataColumn column in columns)
{
string propertyName = column.ColumnName;
FieldBuilder field = typeBuilder.DefineField(propertyName, column.DataType, FieldAttributes.Public);
PropertyBuilder property = typeBuilder.DefineProperty(propertyName, System.Reflection.PropertyAttributes.None, column.DataType, new Type[] { column.DataType });
MethodAttributes GetSetAttr = MethodAttributes.Public | MethodAttributes.HideBySig;
MethodBuilder currGetPropMthdBldr = typeBuilder.DefineMethod("get_value", GetSetAttr, column.DataType, new Type[] { column.DataType }); //Type.EmptyTypes);
ILGenerator currGetIL = currGetPropMthdBldr.GetILGenerator();
currGetIL.Emit(OpCodes.Ldarg_0);
currGetIL.Emit(OpCodes.Ldfld, field);
currGetIL.Emit(OpCodes.Ret);
MethodBuilder currSetPropMthdBldr = typeBuilder.DefineMethod("set_value", GetSetAttr, null, new Type[] { column.DataType });
ILGenerator currSetIL = currSetPropMthdBldr.GetILGenerator();
currSetIL.Emit(OpCodes.Ldarg_0);
currSetIL.Emit(OpCodes.Ldarg_1);
currSetIL.Emit(OpCodes.Stfld, field);
currSetIL.Emit(OpCodes.Ret);
property.SetGetMethod(currGetPropMthdBldr);
property.SetSetMethod(currSetPropMthdBldr);
}
Type obj = typeBuilder.CreateType();
return obj;
}      
}

OriginalL'auteur ChinaHelloWorld

essayer

var MyResult = from x in MyDataTable select new { ID = x["ID"], Name = x["Name"] }.ToList ();

OriginalL'auteur Yahia

Vous pouvez utiliser une extension comme ceci:

using System;
using System.Collections.Generic;
using System.Data;
using System.Dynamic;
public static class DataTableExtensions
{
public static IEnumerable<dynamic> AsDynamicEnumerable(this DataTable table)
{
if (table == null)
{
yield break;
}
foreach (DataRow row in table.Rows)
{
IDictionary<string, object> dRow = new ExpandoObject();
foreach (DataColumn column in table.Columns)
{
var value = row[column.ColumnName];
dRow[column.ColumnName] = Convert.IsDBNull(value) ? null : value;
}
yield return dRow;
}
}
}

Utilisation:

var dataTable = GetDataTableFromSomewhere();
var dynamicTable = dataTable.AsDynamicEnumerable();
var firstRowIDColumn = dynamicTable.First().ID;
var lastRowIDColumn = dynamicTable.Last()["ID"];

Mais j'ai préféré un IDataReader approche si possible.

OriginalL'auteur mehyaa