Asp.net mvc 如何使dropdownlist在asp.net mvc中显示选定值?
我有一个编辑页面,里面有一个Html.DropDownList…我不能显示它总是显示在Asp.net mvc 如何使dropdownlist在asp.net mvc中显示选定值?,asp.net-mvc,drop-down-menu,findby,Asp.net Mvc,Drop Down Menu,Findby,我有一个编辑页面,里面有一个Html.DropDownList…我不能显示它总是显示在Select中的DropDownList值,而是我想让下拉列表显示一个基于模型值选择的项目,比如model.Mes\u Id。。。任何关于如何做的建议 <p> <label for="MeasurementTypeId">MeasurementType:</label> <%= Html.DropDownList(
Select
中的DropDownList值,而是我想让下拉列表显示一个基于模型值选择的项目,比如model.Mes\u Id
。。。任何关于如何做的建议
<p>
<label for="MeasurementTypeId">MeasurementType:</label>
<%= Html.DropDownList("MeasurementType", // what should i give here?)%>
<%= Html.ValidationMessage("MeasurementTypeId", "*") %>
</p>
我的存储库方法
public IEnumerable<SelectListItem> FindAllMeasurements()
{
var mesurements = from mt in db.MeasurementTypes
select new SelectListItem
{
Value = mt.Id.ToString(),
Text= mt.Name
};
return mesurements;
}
public IEnumerable FindAllMeasurements()
{
var测量=以db为单位的mt测量类型
选择新的SelectListItem
{
值=mt.Id.ToString(),
Text=机器名
};
回报测量;
}
看看这篇博客文章
基本上,您需要将测量类型
列表/枚举转换为选择列表
或IEnumerable
如果可能的话,我建议升级到ASP.NET MVC2并使用
Html.DropDownListFor()
查看此博客条目
基本上,您需要将测量类型
列表/枚举转换为选择列表
或IEnumerable
如果可能的话,我建议升级到ASP.NET MVC2,并使用
Html.DropDownListFor()
您应该返回一个可以指定所选项目的SelectionList
您应该返回一个可指定所选项目的SelectionList
假设Model.Mes\u Id包含所选值,您可以执行以下操作
<%
var Measurements = new SelectList((IEnumerable)ViewData["MeasurementType"], "Id", "Name", Model.Mes_Id);
Response.Write(Html.DropDownList("measurement_type", Measurements, "Select"));
%>
(in Edit method )
CreatList(long.Parse(wc.ParentID.ToString()));
private void CreatList(long selected= 0)
{
SqlConnection conn = new SqlConnection(Config.ConnectionStringSimple);
conn.Open();
Category wn = new Category(conn);
CategoryCollection coll = new CategoryCollection();
Category.FetchList(conn, ref coll);
ViewBag.ParentID = GetList(coll, selected);
}
private List<SelectListItem> GetList(CategoryCollection coll, long selected)
{
List<SelectListItem> st = new List<SelectListItem>();
foreach (var cat in coll)
{
st.Add( new SelectListItem
{
Text = cat.Name,
Value = cat.ID.ToString(),
Selected = cat.ID == selected
});
}
SelectListItem s = new SelectListItem {
Text = Resources.lblSelect,
Value = "0"
};
st.Insert(0, s);
return st;
}
<div class="editor-label">
@Html.LabelFor(model => model.ParentID)
</div>
<div class="editor-field">
@Html.DropDownList("ddlCat", (List<SelectListItem>)ViewBag.ParentID)
@Html.ValidationMessageFor(model => model.ParentID)
</div>
假设Model.Mes\u Id包含所选值,您可以执行以下操作
<%
var Measurements = new SelectList((IEnumerable)ViewData["MeasurementType"], "Id", "Name", Model.Mes_Id);
Response.Write(Html.DropDownList("measurement_type", Measurements, "Select"));
%>
(in Edit method )
CreatList(long.Parse(wc.ParentID.ToString()));
private void CreatList(long selected= 0)
{
SqlConnection conn = new SqlConnection(Config.ConnectionStringSimple);
conn.Open();
Category wn = new Category(conn);
CategoryCollection coll = new CategoryCollection();
Category.FetchList(conn, ref coll);
ViewBag.ParentID = GetList(coll, selected);
}
private List<SelectListItem> GetList(CategoryCollection coll, long selected)
{
List<SelectListItem> st = new List<SelectListItem>();
foreach (var cat in coll)
{
st.Add( new SelectListItem
{
Text = cat.Name,
Value = cat.ID.ToString(),
Selected = cat.ID == selected
});
}
SelectListItem s = new SelectListItem {
Text = Resources.lblSelect,
Value = "0"
};
st.Insert(0, s);
return st;
}
<div class="editor-label">
@Html.LabelFor(model => model.ParentID)
</div>
<div class="editor-field">
@Html.DropDownList("ddlCat", (List<SelectListItem>)ViewBag.ParentID)
@Html.ValidationMessageFor(model => model.ParentID)
</div>
在创建
IEnumerable
时设置所选项目
就我个人而言,我会为表单创建一个专门的viewmodel,但根据您的代码,执行以下操作:
public ActionResult Edit(int id)
{
//Put this first
var material = consRepository.GetMaterial(id);
//pass in your selected item
var mesurementTypes = consRepository.FindAllMeasurements(material.MeasurementTypeId);
ViewData["MeasurementType"] = mesurementTypes;
return View("Edit", material);
}
public IEnumerable<SelectListItem> FindAllMeasurements(int selectedId)
{
var mesurements = from mt in db.MeasurementTypes
select new SelectListItem
{
Value = mt.Id.ToString(),
Text= mt.Name,
Selected = mt.Id == selectedId
};
return mesurements;
}
然后将您的存储库方法更改为:
public ActionResult Edit(int id)
{
//Put this first
var material = consRepository.GetMaterial(id);
//pass in your selected item
var mesurementTypes = consRepository.FindAllMeasurements(material.MeasurementTypeId);
ViewData["MeasurementType"] = mesurementTypes;
return View("Edit", material);
}
public IEnumerable<SelectListItem> FindAllMeasurements(int selectedId)
{
var mesurements = from mt in db.MeasurementTypes
select new SelectListItem
{
Value = mt.Id.ToString(),
Text= mt.Name,
Selected = mt.Id == selectedId
};
return mesurements;
}
public IEnumerable FindAllMeasurements(int-selectedId)
{
var测量=以db为单位的mt测量类型
选择新的SelectListItem
{
值=mt.Id.ToString(),
Text=机器名称,
所选=机器识别号==所选识别号
};
回报测量;
}
HTHs,Charles在创建
IEnumerable
时设置所选项目
就我个人而言,我会为表单创建一个专门的viewmodel,但根据您的代码,执行以下操作:
public ActionResult Edit(int id)
{
//Put this first
var material = consRepository.GetMaterial(id);
//pass in your selected item
var mesurementTypes = consRepository.FindAllMeasurements(material.MeasurementTypeId);
ViewData["MeasurementType"] = mesurementTypes;
return View("Edit", material);
}
public IEnumerable<SelectListItem> FindAllMeasurements(int selectedId)
{
var mesurements = from mt in db.MeasurementTypes
select new SelectListItem
{
Value = mt.Id.ToString(),
Text= mt.Name,
Selected = mt.Id == selectedId
};
return mesurements;
}
然后将您的存储库方法更改为:
public ActionResult Edit(int id)
{
//Put this first
var material = consRepository.GetMaterial(id);
//pass in your selected item
var mesurementTypes = consRepository.FindAllMeasurements(material.MeasurementTypeId);
ViewData["MeasurementType"] = mesurementTypes;
return View("Edit", material);
}
public IEnumerable<SelectListItem> FindAllMeasurements(int selectedId)
{
var mesurements = from mt in db.MeasurementTypes
select new SelectListItem
{
Value = mt.Id.ToString(),
Text= mt.Name,
Selected = mt.Id == selectedId
};
return mesurements;
}
public IEnumerable FindAllMeasurements(int-selectedId)
{
var测量=以db为单位的mt测量类型
选择新的SelectListItem
{
值=mt.Id.ToString(),
Text=机器名称,
所选=机器识别号==所选识别号
};
回报测量;
}
HTHs,CharlesHtml.DropDownListFor对我不起作用,所以我得到了这样的罂粟花
<%
var Measurements = new SelectList((IEnumerable)ViewData["MeasurementType"], "Id", "Name", Model.Mes_Id);
Response.Write(Html.DropDownList("measurement_type", Measurements, "Select"));
%>
(in Edit method )
CreatList(long.Parse(wc.ParentID.ToString()));
private void CreatList(long selected= 0)
{
SqlConnection conn = new SqlConnection(Config.ConnectionStringSimple);
conn.Open();
Category wn = new Category(conn);
CategoryCollection coll = new CategoryCollection();
Category.FetchList(conn, ref coll);
ViewBag.ParentID = GetList(coll, selected);
}
private List<SelectListItem> GetList(CategoryCollection coll, long selected)
{
List<SelectListItem> st = new List<SelectListItem>();
foreach (var cat in coll)
{
st.Add( new SelectListItem
{
Text = cat.Name,
Value = cat.ID.ToString(),
Selected = cat.ID == selected
});
}
SelectListItem s = new SelectListItem {
Text = Resources.lblSelect,
Value = "0"
};
st.Insert(0, s);
return st;
}
<div class="editor-label">
@Html.LabelFor(model => model.ParentID)
</div>
<div class="editor-field">
@Html.DropDownList("ddlCat", (List<SelectListItem>)ViewBag.ParentID)
@Html.ValidationMessageFor(model => model.ParentID)
</div>
(在编辑方法中)
CreatList(long.Parse(wc.ParentID.ToString());
私有void创建列表(长选中=0)
{
SqlConnection conn=新的SqlConnection(Config.ConnectionStringSimple);
conn.Open();
类别wn=新类别(康涅狄格州);
CategoryCollection coll=新的CategoryCollection();
类别。获取列表(conn,ref coll);
ViewBag.ParentID=GetList(coll,选中);
}
私有列表GetList(类别集合集合集合,长选中)
{
List st=新列表();
foreach(coll中的var cat)
{
st.Add(新建SelectListItem)
{
Text=cat.Name,
Value=cat.ID.ToString(),
已选择=类别ID==已选择
});
}
SelectListItems=新建SelectListItem{
Text=Resources.lblSelect,
Value=“0”
};
圣插入(0,s);
返回st;
}
@LabelFor(model=>model.ParentID)
@DropDownList(“ddlCat”,(列表)ViewBag.ParentID)
@Html.ValidationMessageFor(model=>model.ParentID)
Html.DropDownListFor对我不起作用,所以我得到了这样的罂粟花
<%
var Measurements = new SelectList((IEnumerable)ViewData["MeasurementType"], "Id", "Name", Model.Mes_Id);
Response.Write(Html.DropDownList("measurement_type", Measurements, "Select"));
%>
(in Edit method )
CreatList(long.Parse(wc.ParentID.ToString()));
private void CreatList(long selected= 0)
{
SqlConnection conn = new SqlConnection(Config.ConnectionStringSimple);
conn.Open();
Category wn = new Category(conn);
CategoryCollection coll = new CategoryCollection();
Category.FetchList(conn, ref coll);
ViewBag.ParentID = GetList(coll, selected);
}
private List<SelectListItem> GetList(CategoryCollection coll, long selected)
{
List<SelectListItem> st = new List<SelectListItem>();
foreach (var cat in coll)
{
st.Add( new SelectListItem
{
Text = cat.Name,
Value = cat.ID.ToString(),
Selected = cat.ID == selected
});
}
SelectListItem s = new SelectListItem {
Text = Resources.lblSelect,
Value = "0"
};
st.Insert(0, s);
return st;
}
<div class="editor-label">
@Html.LabelFor(model => model.ParentID)
</div>
<div class="editor-field">
@Html.DropDownList("ddlCat", (List<SelectListItem>)ViewBag.ParentID)
@Html.ValidationMessageFor(model => model.ParentID)
</div>
(在编辑方法中)
CreatList(long.Parse(wc.ParentID.ToString());
私有void创建列表(长选中=0)
{
SqlConnection conn=新的SqlConnection(Config.ConnectionStringSimple);
conn.Open();
类别wn=新类别(康涅狄格州);
CategoryCollection coll=新的CategoryCollection();
类别。获取列表(conn,ref coll);
ViewBag.ParentID=GetList(coll,选中);
}
私有列表GetList(类别集合集合集合,长选中)
{
List st=新列表();
foreach(coll中的var cat)
{
st.Add(新建SelectListItem)
{
Text=cat.Name,
Value=cat.ID.ToString(),
已选择=类别ID==已选择
});
}
SelectListItems=新建SelectListItem{
Text=Resources.lblSelect,
Value=“0”
};
圣插入(0,s);
返回st;
}
@LabelFor(model=>model.ParentID)
@DropDownList(“ddlCat”,(列表)ViewBag.ParentID)
@Html.ValidationMessageFor(model=>model.ParentID)
请提供更多详细信息。你发布的代码完全符合它的要求。使用一个选项创建标记,其值为“选择”。你想完成什么?注意HTML.DROPPDRONT有9个重载。@ John考虑我的下拉列表包含9个项目…code>Model.Mes_Id=5我想选择值为5的度量类型<