Question

调试c#程序，跳出 标准表达式中数据类型不匹配。部分代码如下：

string strConnection2 = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=db_wygl.mdb";
OleDbConnection objConnection2 = new OleDbConnection(strConnection2); //建立连接
objConnection2.Open();
string sql2 = "select * from tab_smoney where 计费起始日期='#" + dateTimePicker1.Value.ToString("yyyy-MM-dd") + "#'and 计费终止日期='#" + dateTimePicker2.Value.ToString("yyyy-MM-dd") + "#'";
OleDbDataAdapter myda2 = new OleDbDataAdapter(sql2, objConnection2);
DataSet myds2 = new DataSet();
myda2.Fill(myds2,"计费起始日期");
dataGridView1.DataSource = myds2.Tables["计费起始日期"];
objConnection2.Close();

Answer 1

string sql2 = "select * from tab_smoney where 计费起始日期='#" + dateTimePicker1.Value.ToString("yyyy-MM-dd") + "#'and 计费终止日期='#" + dateTimePicker2.Value.ToString("yyyy-MM-dd") + "#'";

计费起始日期这个字段是不是日期类型的，如果是的话，你后面的应该再转成DateTime类型

追问

计费起始日期 是短日期型的，你说的后面的应该再转成DateTime类型，我刚接触不太明白，能说仔细些吗？谢谢

追答

dateTimePicker1.Value.ToString("yyyy-MM-dd")改成：

DateTime.Parse(dateTimePicker1.Value.ToString("yyyy-MM-dd"))