public async static Task <DbTable> ToDbTableAsync(IDataReaderWrapper dataReader)
{
DbTable dbTable = new DbTable();
InitDbTableColumns(dataReader, dbTable);
while (await dataReader.ReadAsync())
{
var dbRow = dbTable.AddRow();
for (int i = 0; i < dataReader.FieldCount; i++)
{
var colName = dataReader.GetName(i);
dbRow[colName] = dataReader[colName];
}
}
return(dbTable);
}
private Func<IDataReader, RequestContext, object> CreateParserImpl(IDataReaderWrapper dataReader, RequestContext context, Type targetType)
{
var statement = context.Statement;
var resultMap = statement?.ResultMap;
resultMap = statement?.MultipleResultMap?.Results.FirstOrDefault(m => m.Index == dataReader.ResultIndex)?.Map ?? resultMap;
var constructorMap = resultMap?.Constructor;
var columns = Enumerable.Range(0, dataReader.FieldCount)
.Select(i => new { Index = i, Name = dataReader.GetName(i) })
.ToDictionary((col) => col.Name);
var dynamicMethod = new DynamicMethod("Deserialize" + Guid.NewGuid().ToString("N"), targetType, new[] { TypeUtils.DataReaderType, TypeUtils.RequestContextType }, targetType, true);
var iLGenerator = dynamicMethod.GetILGenerator();
iLGenerator.DeclareLocal(targetType);
ConstructorInfo targetCtor = null;
if (constructorMap == null)
{
targetCtor = targetType.GetConstructor(
BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null);
}
else
{
var ctorArgTypes = constructorMap.Args.Select(arg => arg.ArgType).ToArray();
targetCtor = targetType.GetConstructor(
BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, ctorArgTypes, null);
//load arg value
foreach (var arg in constructorMap.Args)
{
var col = columns[arg.Column];
EmitLoadColVal(iLGenerator, dataReader, col.Index, arg.TypeHandler, arg.ArgType, null);
}
}
if (targetCtor == null)
throw new SmartSqlException($"No parameterless constructor defined for the target type: \"{targetType.FullName}\"");
iLGenerator.Emit(OpCodes.Newobj, targetCtor); // [target]
iLGenerator.Emit(OpCodes.Stloc_0);
foreach (var col in columns)
{
var colName = col.Key;
var colIndex = col.Value.Index;
var result = resultMap?.Properties?.FirstOrDefault(r => r.Column == colName);
string propertyName = result != null ? result.Name : colName;
var property = targetType.GetProperty(propertyName);
if (property == null) { continue; }
if (!property.CanWrite) { continue; }
Type propertyType = property.PropertyType;
Label isDbNullLabel = iLGenerator.DefineLabel();
EmitLoadColVal(iLGenerator, dataReader, colIndex, result?.TypeHandler, propertyType, isDbNullLabel);
iLGenerator.Emit(OpCodes.Call, property.SetMethod);// stack is empty
iLGenerator.MarkLabel(isDbNullLabel);
}
iLGenerator.Emit(OpCodes.Ldloc_0);// stack is [rval]
iLGenerator.Emit(OpCodes.Ret);
var funcType = System.Linq.Expressions.Expression.GetFuncType(TypeUtils.DataReaderType, TypeUtils.RequestContextType, targetType);
return (Func<IDataReader, RequestContext, object>)dynamicMethod.CreateDelegate(funcType);
}