/// <summary>
/// 根据传入的条件对表查询并返回对象集合
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="conditions"></param>
/// <returns></returns>
public virtual List <T> LoadByCondition <T>(KeyValuePair <string, object>[] conditions, Expression <Func <T, object> > orderBy = null, string orderType = "asc") where T : ModelBase
{
List <T> result = new List <T>();
Type t = typeof(T);
List <string> orders = new List <string>();
if (orderBy != null) //有传排序属性就按排序属性排序
{
orders.Add(ExpressionHandle.DealGetPropertyNameExpression <T>(orderBy));
}
else //否则按主键排序
{
var props = t.GetProperties();
foreach (var p in props)
{
if (p.IsDefined(typeof(MyPrimaryKeyAttribute)))
{
orders.Add(p.Name);
}
}
}
// 获取作为条件的属性的属性名
string[] propNms = GetKeysArray(conditions);
string[] order = orders.ToArray();
string sql = stringBuilder.SelectByCondition(GetTableName(t), propNms, order, orderType);
OpenConnection();
var table = helper.DoSelect(sql, conditions);
initObjectList <T>(result, table);
helper.ShutDown();
return(result);
}
/// <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);
}
/// <summary>
/// 对表进行分页查询并返回对象集合
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="pageSize">每页记录数</param>
/// <param name="nowPage">目前在第几页</param>
/// <param name="infoCount">记录总数</param>
/// <param name="condition">查询条件</param>
/// <param name="orderBy">排序</param>
/// <param name="orderType">排序类型:asc,desc</param>
/// <returns></returns>
public virtual List <T> LoadPageList <T>(int pageSize, int nowPage, ref int infoCount, KeyValuePair <string, object>[] conditions = null, Expression <Func <T, object> > orderBy = null, string orderType = "asc") where T : ModelBase
{
var result = new List <T>();
OpenConnection();
var tragetType = typeof(T);
List <string> orders = new List <string>();
if (orderBy != null) //有传排序属性就按排序属性排序
{
orders.Add(ExpressionHandle.DealGetPropertyNameExpression <T>(orderBy));
}
else //否则按主键排序
{
Type t = typeof(T);
var props = t.GetProperties();
foreach (var p in props)
{
if (p.IsDefined(typeof(MyPrimaryKeyAttribute)))
{
orders.Add(p.Name);
}
}
}
string[] order = orders.ToArray();
string sql = "";// BuildPageSelectSql();
string[] propNms = GetKeysArray(conditions);
if (conditions == null)
{
sql = stringBuilder.SelectPageList(tragetType.Name, pageSize, nowPage, order, orderType);
}
else
{
sql = stringBuilder.SelectPageListWithCondition(tragetType.Name, pageSize, nowPage, propNms, order, orderType);
}
var table = helper.DoSelect(sql, conditions);
initObjectList <T>(result, table);
if (table.Rows.Count > 0)
{
infoCount = Convert.ToInt32(table.Rows[0]["cnt"]);
}
helper.ShutDown();
return(result);
}
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);
}
private void btn_Count_Click(object sender, RoutedEventArgs e)
{
txt_AnswerTextBlock.Text = "";
ExpressionHandle hl = new ExpressionHandle();
List <RealNum> ListExp = new List <RealNum>();
BaseEquation eqtools = new BaseEquation();
if (!eqtools.BalanceChecker(inputBox.Text))
{
showInformation("ERROR", "表达式括号不平衡");
return;
}
ListExp = hl.MakeEasy(inputBox.Text);
string result = GetResult(ListExp);
txt_AnswerTextBlock.Text = result;
}
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);
}
public WhereClause(ExpressionHandle<bool> predicate) {
this.predicate = predicate;
}
