public TResult Execute <TResult>(Expression expression)
{
var stackCallExps = new Stack <MethodCallExpression>();
var callExp = expression as MethodCallExpression;
while (callExp != null)
{
stackCallExps.Push(callExp);
callExp = callExp?.Arguments.FirstOrDefault() as MethodCallExpression;
}
SelectGroupingProvider groupBy = null;
var isfirst = false;
while (stackCallExps.Any())
{
callExp = stackCallExps.Pop();
TResult throwCallExp(string message) => throw new Exception($"FreeSql Queryable 解析出错，执行的方法 {callExp.Method.Name} {message}");
if (callExp.Method.DeclaringType != typeof(Queryable))
{
return(throwCallExp($"必须属于 System.Linq.Queryable"));
}
TResult tplMaxMinAvgSum(string method)
{
if (callExp.Arguments.Count == 2)
{
var avgParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
return((TResult)Utils.GetDataReaderValue(typeof(TResult),
_select.GetType().GetMethod(method).MakeGenericMethod(avgParam.ReturnType).Invoke(_select, new object[] { avgParam })));
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
}
TResult tplOrderBy(string method, bool isDescending)
{
if (callExp.Arguments.Count == 2)
{
var arg1 = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
_select.OrderByReflection(arg1, isDescending);
return(default(TResult));
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
}
switch (callExp.Method.Name)
{
case "Any":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
return((TResult)(object)_select.Any());
case "AsQueryable":
break;
case "Max": return(tplMaxMinAvgSum("Max"));
case "Min": return(tplMaxMinAvgSum("Min"));
case "Sum": return(tplMaxMinAvgSum("Sum"));
case "Average": return(tplMaxMinAvgSum("Avg"));
case "Concat":
return(throwCallExp(" 不支持"));
case "Contains":
if (callExp.Arguments.Count == 2)
{
var dywhere = callExp.Arguments[1].GetConstExprValue();
if (dywhere == null)
{
return(throwCallExp($" 参数值不能为 null"));
}
_select.WhereDynamic(dywhere);
return((TResult)(object)_select.Any());
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "Count":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
return((TResult)Utils.GetDataReaderValue(typeof(TResult), _select.Count()));
case "Distinct":
if (callExp.Arguments.Count == 1)
{
_select.Distinct();
break;
}
return(throwCallExp(" 不支持"));
case "ElementAt":
case "ElementAtOrDefault":
_select.Offset((int)callExp.Arguments[1].GetConstExprValue());
_select.Limit(1);
isfirst = true;
break;
case "First":
case "FirstOrDefault":
case "Single":
case "SingleOrDefault":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
_select.Limit(1);
isfirst = true;
break;
case "OrderBy":
tplOrderBy("OrderByReflection", false);
break;
case "OrderByDescending":
tplOrderBy("OrderByReflection", true);
break;
case "ThenBy":
tplOrderBy("OrderByReflection", false);
break;
case "ThenByDescending":
tplOrderBy("OrderByReflection", true);
break;
case "Where":
var whereParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
if (whereParam.Parameters.Count == 1)
{
if (groupBy != null)
{
groupBy.InternalHaving(whereParam);
}
else
{
_select.InternalWhere(whereParam);
}
break;
}
return(throwCallExp(" 不支持"));
case "Skip":
_select.Offset((int)callExp.Arguments[1].GetConstExprValue());
break;
case "Take":
_select.Limit((int)callExp.Arguments[1].GetConstExprValue());
break;
case "ToList":
if (callExp.Arguments.Count == 1)
{
return((TResult)(object)_select.ToList());
}
return(throwCallExp(" 不支持"));
case "Select":
var selectParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
if (selectParam.Parameters.Count == 1)
{
_select._selectExpression = selectParam;
break;
}
return(throwCallExp(" 不支持"));
case "Join":
if (callExp.Arguments.Count == 5)
{
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
var arg3 = (callExp.Arguments[3] as UnaryExpression)?.Operand as LambdaExpression;
var arg4 = (callExp.Arguments[4] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalJoin2(_select, arg2, arg3, arg4);
_select._selectExpression = arg4.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "GroupJoin":
if (callExp.Arguments.Count == 5)
{
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
var arg3 = (callExp.Arguments[3] as UnaryExpression)?.Operand as LambdaExpression;
var arg4 = (callExp.Arguments[4] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalJoin2(_select, arg2, arg3, arg4);
_select._selectExpression = arg4.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "SelectMany":
if (callExp.Arguments.Count == 3)
{
var arg1 = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalSelectMany2(_select, arg1, arg2);
_select._selectExpression = arg2.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "DefaultIfEmpty":
break;
case "Last":
case "LastOrDefault":
return(throwCallExp(" 不支持"));
case "GroupBy":
return(throwCallExp(" 不支持"));
if (callExp.Arguments.Count == 2) //TODO: 待实现
{
var arg1 = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
var map = new ReadAnonymousTypeInfo();
var field = new StringBuilder();
var index = -10000; //临时规则，不返回 as1
_select._commonExpression.ReadAnonymousField(_select._tables, field, map, ref index, arg1, null, _select._whereCascadeExpression, false); //不走 DTO 映射
var sql = field.ToString();
_select.GroupBy(sql.Length > 0 ? sql.Substring(2) : null);
groupBy = new SelectGroupingProvider(_select._orm, _select, map, sql, _select._commonExpression, _select._tables);
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
default:
return(throwCallExp(" 不支持"));
}
}
if (isfirst)
{
_select.Limit(1);
if (_select._selectExpression != null)
{
return((TResult)(object)_select.InternalToList <TCurrent>(_select._selectExpression).FirstOrDefault());
}
return((TResult)(object)_select.ToList().FirstOrDefault());
}
if (_select._selectExpression != null)
{
return((TResult)(object)_select.InternalToList <TCurrent>(_select._selectExpression));
}
return((TResult)(object)_select.ToList());
}
public object ExecuteExp(Expression expression, Type tresult, bool isProcessed)
{
var callExp = expression as MethodCallExpression;
var isfirst = false;
if (callExp != null && isProcessed == false)
{
object throwCallExp(string message) => throw new Exception($"解析失败 {callExp.Method.Name} {message}，提示：可以使用扩展方法 IQueryable.RestoreToSelect() 还原为 ISelect 再查询");
if (callExp.Method.DeclaringType != typeof(Queryable))
{
return(throwCallExp($"必须属于 System.Linq.Queryable"));
}
object tplMaxMinAvgSum(string method)
{
if (callExp.Arguments.Count == 2)
{
var avgParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
return(Utils.GetDataReaderValue(tresult,
_select.GetType().GetMethod(method).MakeGenericMethod(avgParam.ReturnType).Invoke(_select, new object[] { avgParam })));
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
}
object tplOrderBy(string method, bool isDescending)
{
if (callExp.Arguments.Count == 2)
{
var arg1 = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
_select.OrderByReflection(arg1, isDescending);
return(tresult.CreateInstanceGetDefaultValue());
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
}
switch (callExp.Method.Name)
{
case "Any":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
return(_select.Any());
case "AsQueryable":
break;
case "Max": return(tplMaxMinAvgSum("Max"));
case "Min": return(tplMaxMinAvgSum("Min"));
case "Sum": return(tplMaxMinAvgSum("Sum"));
case "Average": return(tplMaxMinAvgSum("Avg"));
case "Concat":
return(throwCallExp(" 不支持"));
case "Contains":
if (callExp.Arguments.Count == 2)
{
var dywhere = callExp.Arguments[1].GetConstExprValue();
if (dywhere == null)
{
return(throwCallExp($" 参数值不能为 null"));
}
_select.WhereDynamic(dywhere);
return(_select.Any());
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "Count":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
return(Utils.GetDataReaderValue(tresult, _select.Count()));
case "Distinct":
if (callExp.Arguments.Count == 1)
{
_select.Distinct();
break;
}
return(throwCallExp(" 不支持"));
case "ElementAt":
case "ElementAtOrDefault":
_select.Offset((int)callExp.Arguments[1].GetConstExprValue());
_select.Limit(1);
isfirst = true;
break;
case "First":
case "FirstOrDefault":
case "Single":
case "SingleOrDefault":
if (callExp.Arguments.Count == 2)
{
_select.InternalWhere(callExp.Arguments[1]);
}
_select.Limit(1);
isfirst = true;
break;
case "OrderBy":
tplOrderBy("OrderByReflection", false);
break;
case "OrderByDescending":
tplOrderBy("OrderByReflection", true);
break;
case "ThenBy":
tplOrderBy("OrderByReflection", false);
break;
case "ThenByDescending":
tplOrderBy("OrderByReflection", true);
break;
case "Where":
var whereParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
if (whereParam.Parameters.Count == 1)
{
_select.InternalWhere(whereParam);
break;
}
return(throwCallExp(" 不支持"));
case "Skip":
_select.Offset((int)callExp.Arguments[1].GetConstExprValue());
break;
case "Take":
_select.Limit((int)callExp.Arguments[1].GetConstExprValue());
break;
case "ToList":
if (callExp.Arguments.Count == 1)
{
return(_select.ToList());
}
return(throwCallExp(" 不支持"));
case "Select":
var selectParam = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
if (selectParam.Parameters.Count == 1)
{
_select._selectExpression = selectParam;
break;
}
return(throwCallExp(" 不支持"));
case "Join":
if (callExp.Arguments.Count == 5)
{
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
var arg3 = (callExp.Arguments[3] as UnaryExpression)?.Operand as LambdaExpression;
var arg4 = (callExp.Arguments[4] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalJoin2(_select, arg2, arg3, arg4);
_select._selectExpression = arg4.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "GroupJoin":
if (callExp.Arguments.Count == 5)
{
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
var arg3 = (callExp.Arguments[3] as UnaryExpression)?.Operand as LambdaExpression;
var arg4 = (callExp.Arguments[4] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalJoin2(_select, arg2, arg3, arg4);
_select._selectExpression = arg4.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "SelectMany":
if (callExp.Arguments.Count == 3)
{
var arg1 = (callExp.Arguments[1] as UnaryExpression)?.Operand as LambdaExpression;
var arg2 = (callExp.Arguments[2] as UnaryExpression)?.Operand as LambdaExpression;
FreeSqlExtensionsLinqSql.InternalSelectMany2(_select, arg1, arg2);
_select._selectExpression = arg2.Body;
break;
}
return(throwCallExp($" 不支持 {callExp.Arguments.Count}个参数的方法"));
case "DefaultIfEmpty":
break;
case "Last":
case "LastOrDefault":
return(throwCallExp(" 不支持"));
case "GroupBy":
return(throwCallExp(" 不支持"));
default:
return(throwCallExp(" 不支持"));
}
}
if (tresult == null)
{
return(null);
}
if (isfirst)
{
_select.Limit(1);
if (_select._selectExpression != null)
{
return(_select.InternalToList <TCurrent>(_select._selectExpression).FirstOrDefault());
}
return(_select.ToList().FirstOrDefault());
}
if (_select._selectExpression != null)
{
return(_select.InternalToList <TCurrent>(_select._selectExpression));
}
return(_select.ToList());
}
