/// <summary>
/// 初始化一个<see cref="FilterRule"/>类型的新实例
/// </summary>
/// <param name="field">数据名称</param>
/// <param name="value">数据值</param>
/// <param name="operateCode">操作方式的前台码</param>
public FilterRule(string field, object value, string operateCode)
: this(field, value, FilterHelper.GetFilterOperate(operateCode))
{
}
/// <summary>
/// 获取指定查询条件组的查询表达式
/// </summary>
/// <typeparam name="T">表达式实体类型</typeparam>
/// <param name="group">查询条件组，如果为null，则直接返回 true 表达式</param>
/// <returns>查询表达式</returns>
public virtual Expression <Func <T, bool> > GetExpression <T>(FilterGroup group)
{
return(FilterHelper.GetExpression <T>(group));
}
/// <summary>
/// 获取指定查询条件的查询表达式
/// </summary>
/// <typeparam name="T">表达式实体类型</typeparam>
/// <param name="rule">查询条件，如果为null，则直接返回 true 表达式</param>
/// <returns>查询表达式</returns>
public virtual Expression <Func <T, bool> > GetExpression <T>(FilterRule rule)
{
return(FilterHelper.GetExpression <T>(rule));
}
/// <summary>
/// 验证指定查询条件组是否能正常转换为表达式
/// </summary>
/// <param name="group">查询条件组</param>
/// <param name="type">实体类型</param>
/// <returns>验证操作结果</returns>
public virtual OperationResult CheckFilterGroup(FilterGroup group, Type type)
{
return(FilterHelper.CheckFilterGroup(group, type));
}
/// <summary>
/// 初始化一个<see cref="FilterGroup"/>类型的新实例
/// </summary>
/// <param name="operateCode">条件间操作方式的前台码</param>
public FilterGroup(string operateCode)
: this(FilterHelper.GetFilterOperate(operateCode))
{
}
/// <summary>
/// 将条件转换为查询表达式
/// </summary>
public static Expression <Func <TEntity, bool> > ToExpression <TEntity>(this FilterRule rule)
{
return(FilterHelper.GetExpression <TEntity>(rule));
}
/// <summary>
/// 将条件组转换为查询表达式
/// </summary>
public static Expression <Func <TEntity, bool> > ToExpression <TEntity>(this FilterGroup group)
{
return(FilterHelper.GetExpression <TEntity>(group));
}
/// <summary>
/// 获取指定字段和条件组表达式
/// </summary>
/// <typeparam name="T">表达式实体类型</typeparam>
/// <param name="group">查询条件组，如果为null，则直接返回 true 表达式</param>
/// <param name="filterfields">查询过滤字段集合</param>
/// <returns>查询表达式</returns>
public Expression <Func <T, bool> > GetExpression <T>(FilterGroup group, IDictionary <string, string> filterfields)
{
return(FilterHelper.GetExpression <T>(group, filterfields));
}