我在mvc工作,并在我的视图中有一个表单,从我的viewmodel接收一个selectlist,将值插入我的下拉列表。
但在提交表格时没有任何作用,我无法弄明白它是怎么回事。
在提交表单后,我得到null到我的数据库。
有人可以帮我解决这个问题吗?这是我的代码: 查看:
model MyProject.Models.ViewModel
@using(Html.BeginForm()) {
@Html.DropDownListFor(o => o.cp.Companylist,Model.cp.Companylist)
@Html.EditorFor(o => o.md.title)
@Html.EditorFor(o => o.md.edition)
@Html.EditorFor(o => o.md.number)
<input type="submit" name="submit" value="Add New">
}
控制器:
public ActionResult Create()
{ ViewModel vm = new ViewModel ();
return View(vm);
}
//
// POST: Create
[HttpPost]
public ActionResult Create(Mydata model)
{
if (ModelState.IsValid)
{
db.Res.Add(model);
db.SaveChanges();
return RedirectToAction("Index","AdminPanel");
}
return View(model);
}
型号:
public class ViewModel
{
public Mydata md { get; set; }
public Company cp { get; set; }
}
Mydata - 型号:
public class Mydata
{
public int ID { get; set; }
public string company_name{ get; set; }
public string title{ get; set; }
public string edition{ get; set; }
public string number{ get; set; }
}
public class DefaultConnection : DbContext
{
public DbSet<Mydata> Res{ get; set; }
}
公司 - 型号:
public class Company
{
public int id { get; set; }
public string name{ get; set; }
public SelectList Companylist{ get; set; }
public Company()
{
Companylist= GetCompanies();
}
public SelectList GetCompanies()
{
var list = new List<SelectListItem>();
string connection = ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
using (var con = new SqlConnection(connection))
{
con.Open();
using (var command = new SqlCommand("SELECT * FROM MyCompanies", con))
{
SqlDataReader reader = command.ExecuteReader();
while (reader.Read())
{
//string id = reader[0] as string;
string name_company= reader[1] as string;
list.Add(new SelectListItem() { Text = name_company, Value = name_company});
}
}
con.Close();
}
return new SelectList(list, "Value", "Text");
}
}
答案 0 :(得分:1)
问题是您正在创建ViewModel,但它的md
和cp
属性未初始化。这就是为什么当您在视图中调用o.cp.Companylist
时,o.cp
为空。
由于您尝试Create()
,您可能不希望将现有数据分配给MyData
或Company
,因此您只需确保初始化此属性即可。您可以在ViewModel
构造函数中轻松完成此操作:
public class ViewModel
{
public ViewModel()
{
this.md = new Mydata();
this.cp = new Company();
}
public Mydata md { get; set; }
public Company cp { get; set; }
}