/// <summary>
/// 根据C#表达式构造SQL语句
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="express"></param>
/// <returns></returns>
public virtual KeyValuePair <string, object>[] SelectMany <T>(out string sql, Expression <Func <T, bool> > express, string TableName)
{
var ex = express.Body;
string sqlBase = SelectMany_Base(TableName);
string whereStr = "";
var ret = ExpressionHandle.DealExpression(out whereStr, ex);
sql = sqlBase + whereStr;
return(ret);
}
public virtual KeyValuePair <string, object>[] SelectPageListWithCondition <T>(out string sql, string Table, int pageSize, int nowPage, Expression <Func <T, bool> > condition, string[] orderBy = null, string orderType = "asc")
{
StringBuilder sb = new StringBuilder();
string whereStr = "";
KeyValuePair <string, object>[] conditions = null;
sb.Append("select * from " + Table + ",(select count(*) as cnt from " + Table + ") as T" + " where ");
if (condition != null)
{
conditions = ExpressionHandle.DealExpression(out whereStr, condition.Body);
sb.Append(whereStr);
sb.Append(" and ");
}
sb.Append("1=1 ");
sql = sb.ToString() + OrderByString(orderType, orderBy) + LimitString(pageSize, nowPage);
return(conditions);
}
public override KeyValuePair <string, object>[] SelectPageListWithCondition <T>(out string sql, string Table, int pageSize, int nowPage, Expression <Func <T, bool> > condition, string[] orderBy = null, string orderType = "asc")
{
KeyValuePair <string, object>[] ret = null;
string whereStr = "";
StringBuilder sb = new StringBuilder();
sb.Append(" where ");
if (condition != null)
{
ret = ExpressionHandle.DealExpression(out whereStr, condition.Body);
sb.Append(whereStr);
sb.Append(" and ");
}
sb.Append("1=1 ");
whereStr = sb.ToString();
int star = (nowPage - 1) * pageSize + 1;
int end = star + pageSize - 1;
sql = "select * from(select ROW_NUMBER()over(" + OrderByString(orderType, orderBy) + ") rowID,* from " + Table + " " + whereStr + ") as tbq,(select count(*) cnt from " + Table + ") as tb where tbq.rowID between " + star + " and " + end + ";";
return(ret);
}
