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public byte GetByte(int i) => (byte)GetValue(i);
public string GetName(int i) => ModelToDataTable<TModel>.Columns[i].ColumnName;
public string GetDataTypeName(int i) => ModelToDataTable<TModel>.Columns[i].DataType.Name;
public Type GetFieldType(int i) => ModelToDataTable<TModel>.Columns[i].DataType;
public object GetValue(int i) => _currentDataRow[i];
public bool GetBoolean(int i) => (bool)GetValue(i);
public char GetChar(int i) => (char)GetValue(i);
public Guid GetGuid(int i) => (Guid)GetValue(i);
public short GetInt16(int i) => (short)GetValue(i);
public int GetInt32(int i) => (int)GetValue(i);
public long GetInt64(int i) => (long)GetValue(i);
public float GetFloat(int i) => (float)GetValue(i);
public double GetDouble(int i) => (double)GetValue(i);
public string GetString(int i) => (string)GetValue(i);
public decimal GetDecimal(int i) => (decimal)GetValue(i);
public DateTime GetDateTime(int i) => (DateTime)GetValue(i);
public IDataReader GetData(int i) => throw new NotSupportedException();
public int FieldCount => ModelToDataTable<TModel>.Columns.Count;
public object this[int i] => GetValue(i);
public object this[string name] => GetValue(GetOrdinal(name));
public void Close() => Dispose();
public DataTable GetSchemaTable() => ModelToDataTable<TModel>.ToDataTable(_source);
public bool Read() => NextResult();
public int Depth => _depth;
public bool IsClosed => _release;
public int RecordsAffected => 0;
}
模型对象转数据行工具类
/// <summary>
/// 对象转换成DataTable转换类
/// </summary>
/// <typeparam>泛型类型</typeparam>
public static class ModelToDataTable<TModel>
{
static ModelToDataTable()
{
//如果需要剔除某些列可以修改这段代码
var propertyList = typeof(TModel).GetProperties().Where(w => w.CanRead).ToArray();
Columns = new ReadOnlyCollection<DataColumn>(propertyList
.Select(pr => new DataColumn(pr.Name, GetDataType(pr.PropertyType))).ToArray());
//生成对象转数据行委托
ToRowData = BuildToRowDataDelegation(typeof(TModel), propertyList);
}
/// <summary>
/// 构建转换成数据行委托
/// </summary>
/// <param>传入类型</param>
/// <param>转换的属性</param>
/// <returns>转换数据行委托</returns>
private static Func<TModel, object[]> BuildToRowDataDelegation(Type type, PropertyInfo[] propertyList)
{
var source = Expression.Parameter(type);
var items = propertyList.Select(property => ConvertBindPropertyToData(source, property));
var array = Expression.NewArrayInit(typeof(object), items);
var lambda = Expression.Lambda<Func<TModel, object[]>>(array, source);
return lambda.Compile();
}
/// <summary>
/// 将属性转换成数据
/// </summary>
/// <param>源变量</param>
/// <param>属性信息</param>
/// <returns>获取属性数据表达式</returns>
private static Expression ConvertBindPropertyToData(ParameterExpression source, PropertyInfo property)
{
var propertyType = property.PropertyType;
var expression = (Expression)Expression.Property(source, property);
if (propertyType.IsEnum)
expression = Expression.Convert(expression, propertyType.GetEnumUnderlyingType());
return Expression.Convert(expression, typeof(object));
}
/// <summary>
/// 获取数据类型
/// </summary>
/// <param>属性类型</param>
/// <returns>数据类型</returns>
private static Type GetDataType(Type type)
{
//枚举默认转换成对应的值类型
if (type.IsEnum)
return type.GetEnumUnderlyingType();
//可空类型
if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable<>))
return GetDataType(type.GetGenericArguments().First());
return type;
}
/// <summary>
/// 列集合
/// </summary>
public static IReadOnlyList<DataColumn> Columns { get; }
/// <summary>
/// 对象转数据行委托
/// </summary>
public static Func<TModel, object[]> ToRowData { get; }
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