private TResult ExecuteFirstFunc <TResult>(MethodCallExpression methodCall)
{
List <T> data = null;
if (methodCall.Arguments.Count == 2)
{
var lambda = (methodCall.Arguments[1] as UnaryExpression).Operand as LambdaExpression;
SelectExpressionResolver <T> selectResolver = new SelectExpressionResolver <T>();
WhereExpressionResolver <T> whereResolver = new WhereExpressionResolver <T>();
whereResolver.Resolve(lambda);
if (methodCall.Arguments[0] is MethodCallExpression)
{
ExpressionResolverManager <T> manager = new ExpressionResolverManager <T>(methodCall.Arguments[0] as MethodCallExpression).Resolve();
var sql = $"SELECT TOP 1 {selectResolver.SQL} FROM {typeof(T).TableName()} WHERE {$"{whereResolver.SQL} AND {manager.WhereResolver.SQL}"} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
var parameters = whereResolver.SqlParameters.Concat(manager.WhereResolver.SqlParameters);
data = DatabaseOperator.ExecuteReader <T>(DatabaseOperator.connection, sql, parameters.ToArray());
}
else if (methodCall.Arguments[0] is ConstantExpression)
{
var sql = $"SELECT TOP 1 {selectResolver.SQL} FROM {typeof(T).TableName()} WHERE {whereResolver.SQL}";
data = DatabaseOperator.ExecuteReader <T>(DatabaseOperator.connection, sql, whereResolver.SqlParameters);
}
}
else if (methodCall.Arguments.Count == 1)
{
var manager = new ExpressionResolverManager <T>(methodCall.Arguments[0] as MethodCallExpression).Resolve();
var sql = $"SELECT TOP 1 {manager.SelectResolver.SQL} FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
data = DatabaseOperator.ExecuteReader <T>(DatabaseOperator.connection, sql, manager.WhereResolver.SqlParameters);
}
var ret = Convert.ChangeType((dynamic)data[0], typeof(T));
return((TResult)(object)ret);
}
private TResult ExecuteAllFunc <TResult>(MethodCallExpression methodCall)
{
int countOrigin = 0;
int countAll = 0;
var lambda = (methodCall.Arguments[1] as UnaryExpression).Operand as LambdaExpression;
WhereExpressionResolver <T> whereResolver = new WhereExpressionResolver <T>();
whereResolver.Resolve(lambda);
if (methodCall.Arguments[0] is MethodCallExpression)
{
ExpressionResolverManager <T> manager = new ExpressionResolverManager <T>(methodCall.Arguments[0] as MethodCallExpression).Resolve();
var sqlAll = $"SELECT Count(*) FROM {typeof(T).TableName()} WHERE {$"{whereResolver.SQL} AND {manager.WhereResolver.SQL}"} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
var parameters = whereResolver.SqlParameters.Concat(manager.WhereResolver.SqlParameters);
countAll = (int)DatabaseOperator.ExecuteScalar(DatabaseOperator.connection, sqlAll, parameters.ToArray());
var sqlOrigin = $"SELECT Count(*) FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
countOrigin = (int)DatabaseOperator.ExecuteScalar(DatabaseOperator.connection, sqlOrigin, manager.WhereResolver.SqlParameters);
}
else if (methodCall.Arguments[0] is ConstantExpression)
{
var sqlAll = $"SELECT Count(*) FROM {typeof(T).TableName()} WHERE {whereResolver.SQL}";
countAll = (int)DatabaseOperator.ExecuteScalar(DatabaseOperator.connection, sqlAll, whereResolver.SqlParameters);
var sqlOrigin = $"SELECT Count(*) FROM {typeof(T).TableName()}";
countOrigin = (int)DatabaseOperator.ExecuteScalar(DatabaseOperator.connection, sqlOrigin, whereResolver.SqlParameters);
}
return((TResult)(object)(countAll == countOrigin));
}
private TResult ExecuteCoreQuery <TResult>(MethodCallExpression methodCall)
{
string sql = string.Empty;
var manager = new ExpressionResolverManager <T>(methodCall).Resolve();
if (manager.SkipResolver.Skip > 0 && manager.TakeResolver.Take > 0)
{
sql = $"SELECT {manager.SelectResolver.SQL} FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL} OFFSET {manager.SkipResolver.Skip} ROWS FETCH NEXT {manager.TakeResolver.Take} ROWS ONLY";
}
else if (manager.SkipResolver.Skip > 0 && manager.TakeResolver.Take == 0)
{
sql = $"SELECT {manager.SelectResolver.SQL} FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL} {manager.SkipResolver.SQL}";
}
else if (manager.SkipResolver.Skip == 0 && manager.TakeResolver.Take > 0)
{
sql = $"SELECT {manager.TakeResolver.SQL} {manager.SelectResolver.SQL} FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
}
else
{
sql = $"SELECT {manager.SelectResolver.SQL} FROM {typeof(T).TableName()} WHERE {manager.WhereResolver.SQL} {manager.GroupByResolver.SQL} {manager.OrderByResolver.SQL}";
}
var data = DatabaseOperator.ExecuteReader <T>(DatabaseOperator.connection, sql, manager.WhereResolver.SqlParameters);
// 处理Select语句返回匿名对象
if (manager.SelectResolver.Expression != null)
{
var selctQuery = data.AsQueryable().Provider.CreateQuery(
Expression.Call(typeof(Queryable),
"Select",
new Type[] {
data.AsQueryable().ElementType,
manager.SelectResolver.Expression.Body.Type
},
data.AsQueryable().Expression,
Expression.Quote(manager.SelectResolver.Expression)));
List <object> list = new List <object>();
foreach (var item in selctQuery)
{
list.Add(Convert.ChangeType(item, manager.SelectResolver.Expression.ReturnType));
}
return((TResult)(object)list);
}
return((TResult)(object)data);
}
