Question

ASP.NET关于日期问题的咨询

M_anguizs.anguizs_lastdate这个“anguizs_lastdate”字段是个日期型数据，在添加数据时，我这个字段要为空，等数据审核确定后才能加日期，那么在我最开始添加数据时我应该怎么处理，我用下面几种写法都有问题，帮我看看应该怎么写
M_anguizs.anguizs_lastdate = "";
M_anguizs.anguizs_lastdate = "NULL";
M_anguizs.anguizs_lastdate = DateTime.Parse("");
M_anguizs.anguizs_lastdate = DateTime.Parse("NULL");
这几种写法都报一样的错“类型不匹配”

在线等，能正确解答问题的 一定给分
是写的三层架构
在DAL里有
strSql.Append("insert into T_anguizs(");
strSql.Append("anguizs_kind,anguizs_name,anguizs_date,anguizs_client,anguizs_genus,R1,anguizs_lastdate)");
strSql.Append(" values (");
strSql.Append("@anguizs_kind,@anguizs_name,@anguizs_date,@anguizs_client,@anguizs_genus,@R1,@anguizs_lastdate)");
strSql.Append(";select @@IDENTITY");

所以不能用M_anguizs.anguizs_lastdate = "";

Answer 1

M_anguizs.anguizs_lastdate = DbType.DateTime("");
M_anguizs.anguizs_lastdate = DbType.DateTime("NULL");
我觉得你M_anguizs.anguizs_lastdate = ""; 这条就成了
你可以
strSql.Append("insert into T_anguizs(");
strSql.Append("anguizs_kind,anguizs_name,anguizs_date,anguizs_client,anguizs_genus,R1)");
strSql.Append(" values (");
strSql.Append("@anguizs_kind,@anguizs_name,@anguizs_date,@anguizs_client,@anguizs_genus,@R1)");
strSql.Append(";select @@IDENTITY");
总之是insert语句 和 select语句
update的时候 另写方法

Answer 2

M_anguizs.anguizs_lastdate = TimeParser.ConvertIntDateTime(DateTime.Parse(""));

Answer 3

直接不赋值就可以啦