internal static string GroupByHaving(this AttrBaseResult model)
{
StringBuilder groupbyBuilder = new StringBuilder();
StringBuilder havingBuilder = new StringBuilder();
//拿到所有标记了该特性的字段
groupbyBuilder.Append($" Group By ");
havingBuilder.Append($" Having ");
foreach (var prop in model.GetType().GetProperties())
{
if (prop.IsDefined(typeof(GroupByAttribute), true))
{
GroupByAttribute groupBy = prop.GetCustomAttributes(typeof(GroupByAttribute), true)[0] as GroupByAttribute;
groupbyBuilder.Append($"{groupBy.GetGroupByField()},");
}
if (prop.IsDefined(typeof(HavingAttribute), true))
{
HavingAttribute having = prop.GetCustomAttributes(typeof(HavingAttribute), true)[0] as HavingAttribute;
if (!string.IsNullOrEmpty(having.GetHavingCondition()))
{
havingBuilder.Append($" {having.GetHavingCondition()} And");
}
}
}
if (groupbyBuilder.ToString() == " Group By ")
{
groupbyBuilder.Clear();
return(string.Empty);
}
else
{
groupbyBuilder.Remove(groupbyBuilder.Length - 1, 1);
}
if (havingBuilder.ToString() == " Having ")
{
havingBuilder.Clear();
}
else
{
havingBuilder.Remove(havingBuilder.Length - 3, 3); //移除最后一个And
groupbyBuilder.Append(havingBuilder.ToString());
}
//后面继续完善Having部分
return(groupbyBuilder.ToString());
}
/// <summary>
/// 获取查询字段
/// </summary>
/// <param name="model"></param>
/// <returns></returns>
internal static string Select(this AttrBaseResult model)
{
StringBuilder builder = new StringBuilder();
builder.Append("SELECT ");
foreach (var prop in model.GetType().GetProperties())
{
//如果字段标记非查询属性，则直接跳过
if (prop.IsDefined(typeof(NonSelectAttribute), true))
{
continue;
}
//若该属性没有标记字段，则直接使用该字段
if (prop.GetCustomAttributes(true).Length == 0)
{
builder.Append($"{prop.Name},");
continue;
}
//是否使用函数
if (prop.IsDefined(typeof(NonAggregateFuncFieldAttribute), true))
{
NonAggregateFuncFieldAttribute funcFieldAttribute = prop.GetCustomAttributes(typeof(NonAggregateFuncFieldAttribute), true)[0] as NonAggregateFuncFieldAttribute;
builder.Append($"{funcFieldAttribute.GetNonAggregateFuncField()} AS ");
builder.Append($"{prop.Name},");
continue;
}
//是否使用聚合函数
if (prop.IsDefined(typeof(AggregateFuncFieldAttribute), true))
{
AggregateFuncFieldAttribute funcFieldAttribute = prop.GetCustomAttributes(typeof(AggregateFuncFieldAttribute), true)[0] as AggregateFuncFieldAttribute;
builder.Append($"{funcFieldAttribute.GetAggregateFuncField()} AS ");
builder.Append($"{prop.Name},");
continue;
}
//是否使用运算符操作
if (prop.IsDefined(typeof(OperationAttribute), true))
{
OperationAttribute operation = prop.GetCustomAttributes(typeof(OperationAttribute), true)[0] as OperationAttribute;
builder.Append($"{operation.GetExpression()} AS {prop.Name},");
continue;
}
//表别名.字段名 AS 字段别名
if (prop.IsDefined(typeof(TableByNameAttribute), true))
{
TableByNameAttribute byName = prop.GetCustomAttributes(typeof(TableByNameAttribute), true)[0] as TableByNameAttribute;
builder.Append($"{byName.GetName()}.");
}
if (prop.IsDefined(typeof(DbFieldNameAttribute), true))
{
DbFieldNameAttribute fieldName = prop.GetCustomAttributes(typeof(DbFieldNameAttribute), true)[0] as DbFieldNameAttribute;
builder.Append($"{fieldName.GetDbFieldName()} AS ");
builder.Append($"{prop.Name},");
}
else
{
builder.Append($"{prop.Name},");
}
}
//移除最后一个逗号
builder.Remove(builder.Length - 1, 1);
builder.Append(" ");
return(builder.ToString());
}