C# 从类型'；System.String'；输入''；Y'；失败，因为没有类型转换器可以在这些类型之间转换
我被这个错误绊住了，我检查了值是否为空。当我试图按下保存按钮时，出现了这个错误 请帮助我，这是错误：C# 从类型'；System.String'；输入''；Y'；失败，因为没有类型转换器可以在这些类型之间转换,c#,.net,asp.net-mvc-4,C#,.net,Asp.net Mvc 4,我被这个错误绊住了，我检查了值是否为空。当我试图按下保存按钮时，出现了这个错误 请帮助我，这是错误： The parameter conversion from type 'System.String' to type 'ULIV.ViewModels.NewProposal' failed because no type converter can convert between these types. ModelState.IsValid为false 以下是使用的视图模型： public
The parameter conversion from type 'System.String' to type 'ULIV.ViewModels.NewProposal' failed because no type converter can convert between these types.
public class PurchaseOrderViewModel
{
[Key]
public int ID { get; set; }
public IEnumerable<Institution> Institution { get; set; }
[Required]
public string PurchaseOrderNo { get; set; }
[Required]
public DateTime PurchaseOrderDate { get; set; }
[Required]
public DateTime ReceivedDate { get; set; }
public string Remarks { get; set; }
public IEnumerable<NewProposal> Proposal { get; set; }
public IEnumerable<PODetail> PODetail { get; set; }
public IEnumerable<NewProposal> AddedProposal { get; set; }
}
公共类PurchaseOrderViewModel
{
[关键]
公共int ID{get；set；}
公共IEnumerable机构{get；set；}
[必需]
公共字符串PurchaseOrderNo{get；set；}
[必需]
公共日期时间PurchaseOrderDate{get；set；}
[必需]
公共日期时间接收日期{get；set；}
公共字符串备注{get；set；}
公共IEnumerable建议{get；set；}
公共IEnumerable PODetail{get；set；}
公共IEnumerable AddedProposal{get；set；}
}
[HttpPost]
public ActionResult Create(PurchaseOrderViewModel purchaseorderviewmodel)
{
purchaseorderviewmodel.AddedProposal = (List<ULIV.ViewModels.NewProposal>)Session["AddedProposal"];
//purchaseorderviewmodel.Proposal = db.NewProposal.Where(x => x.Status.StatusID == 3).ToList();
int instituionId = Convert.ToInt32(Session["InstitutionID"]);
purchaseorderviewmodel.Institution = db.Institutions.Where(x => x.InstitutionID == instituionId).ToList();
if (ModelState.IsValid)
{
db.PurchaseOrderViewModels.Add(purchaseorderviewmodel);
db.SaveChanges();
return RedirectToAction("Index","Fulfillment");
}
ViewBag.Proposal = new SelectList(db.NewProposal.Where(x => x.Status.StatusID == 3), "ProposalID", "ProposalCode");
return View(purchaseorderviewmodel);
}
[HttpPost]
公共操作结果创建（PurchaseOrderViewModel PurchaseOrderViewModel）
{
purchaseorderviewmodel.AddedProposal=（列表）会话[“AddedProposal”]；
//purchaseorderviewmodel.Proposal=db.NewProposal.Where（x=>x.Status.StatusID==3.ToList（）；
int InstitutionID=Convert.ToInt32（会话[“InstitutionID]”）；
purchaseorderviewmodel.Institution=db.Institutions.Where（x=>x.InstitutionID==InstitutionID.ToList（）；
if（ModelState.IsValid）
{
db.PurchaseOrderViewModels.Add（purchaseorderviewmodel）；
db.SaveChanges（）；
返回重定向操作（“索引”、“履行”）；
}
ViewBag.Proposal=new SelectList（db.NewProposal.Where（x=>x.Status.StatusID==3），“ProposalID”，“ProposalCode”）；
返回视图（purchaseorderviewmodel）；
}
((List<ULIV.ViewModels.NewProposal>)Session["AddedProposal"]).FirstOrDefault()
DateModified: {1/15/2014 2:57:52 PM}
FinalUnitPrice: 23
FinalVolume: 34
getdatestring: "1/15/2014"
Institution: {System.Data.Entity.DynamicProxies.Institution_B01649AB79941CE0188D081B425698F4FD6629E82FDB13CCE17B03E348459273}
InstitutionID: 1
Product: {ULIV.Models.ProductModel}
ProductID: 1
ProposalCode: "PC-2014-00001"
ProposalID: 1
ProposedUnitPrice: 3
ProposedVolume: "2"
RelatedProposalCode: ""
Remarks: "hello"
Status: {ULIV.Models.Status}
StatusID: 3
VaccineType: {ULIV.Models.VaccineType}
VaccineTypeID: 1
((List<ULIV.ViewModels.NewProposal>)Session["AddedProposal"]).FirstOrDefault()
（（列表）会话[“AddedProposal]”）。FirstOrDefault（）
修改日期：{1/15/2014 2:57:52 PM}
最终价格：23
最终体积：34
getdatestring:“1/15/2014”
机构：{System.Data.Entity.DynamicProxies.Institution_B01649AB79941CE0188D081B425698F4FD6629E82FDB13CCE17B03E348459273}
机构编号：1
产品：{ULIV.Models.ProductModel}
产品编号：1
提议代码：“PC-2014-00001”
提案人：1
建议单价：3
建议卷：“2”
相关提议代码：“
备注：“你好”
状态：{ULIV.Models.Status}
身份证号码：3
疫苗类型：{ULIV.Models.VaccineType}
疫苗种类：1
（（列表）会话[“AddedProposal]”）。FirstOrDefault（）
<div class="row">
@using (Html.BeginForm("Create", "PurchaseOrder",
new { ReturnUrl = ViewBag.ReturnUrl },
FormMethod.Post, new { @class = "form-horizontal" }))
{
@Html.AntiForgeryToken()
@Html.ValidationSummary(true)
<h1 class="subpage-headline font-global">New Purchase Order</h1>
<div class="row">
<h2 class="subpage-headline2 font-global">New Purchase Order</h2>
@*<form class="form-horizontal" role="form">*@
@foreach (var inst in Model.Institution)
{
<div class="row-div">
<div class="form-group">
<label class="col-sm-2 control-label">Institution Name:</label>
<div class="col-sm-3">
<label class="control-text-label">@Html.DisplayFor(modelItem => inst.InstitutionName)</label>
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Account Classifications:</label>
<div class="col-sm-3">
<label class="control-text-label">Private</label>
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Employee Population:</label>
<div class="col-sm-3">
<label class="control-text-label">50</label>
</div>
</div>
</div>
<div class="row-div">
<div class="form-group">
<label class="col-sm-2 control-label">Address:</label>
<div class="col-sm-4">
<label class="control-text-label">Ninoy Aquino Ave. Clark Pampanga Clark Freeport Zone 1500</label>
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Telephone No.:</label>
<div class="col-sm-3">
<label class="control-text-label">599-3146</label>
</div>
</div>
</div>
}
@*</form>*@
@*<form class="form-horizontal" role="form">*@
<div class="form-group">
<label class="col-sm-2 control-label">Purchase Order Number:</label>
<div class="col-sm-4">
@Html.TextBoxFor(model => model.PurchaseOrderNo, new { @class = "form-control", @type = "text" })
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Purchse Order Date:</label>
<div class="col-sm-4">
@Html.TextBoxFor(model => model.PurchaseOrderDate, new { @class = "form-control datepicker", @type = "text" })
</div>
</div>
<div class="row">
<label class="col-sm-2"></label>
<label class="col-sm-2 font-md">Proposal Code <span class="required">*</span></label>
<label class="col-sm-2 font-md">Description <span class="required">*</span></label>
<label class="col-sm-2 font-md">Unit Price w/ VAT <span class="required">*</span></label>
<label class="col-sm-1 font-md">Total Units <span class="required">*</span></label>
<label class="col-sm-2 font-md">Total Amount w/ VAT <span class="required">*</span></label>
<label class="col-sm-1"></label>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Proposal:</label>
<div class="col-sm-2">
@Html.DropDownList("ProposalID", new SelectList(ViewBag.Proposal, "Value", "Text"), "SELECT Proposal", new { @class = "form-control input", @type = "text", @name = "ddlInst" })
</div>
<div class="col-sm-2">
<input type="text" class="form-control" id="prodDesc_0">
</div>
<div class="col-sm-2">
<input type="text" class="form-control" id="unitPrice_0">
</div>
<div class="col-sm-1">
<input type="text" class="form-control" id="totalUnits_0">
</div>
<div class="col-sm-2">
<input type="text" class="form-control" id="totalAmount_0">
</div>
<div class="col-sm-1">
<button type="button" class="btn btn-primary" onclick="AddProposal()">Add</button>
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Product:</label>
<div class="col-sm-9">
<table class="table table-bordered table-hover">
<thead>
<tr class="th-center">
<th>Proposal Code</th>
<th>Description</th>
<th>Unit Price VAT</th>
<th>Total Units</th>
<th>Total Amount w/ VAT</th>
<th>Action</th>
</tr>
</thead>
<tbody>
@Html.HiddenFor(model => model.AddedProposal)
@if (Model.AddedProposal != null)
{
foreach (var prop in Model.AddedProposal)
{
<tr class="text-center">
<td>@Html.DisplayFor(modelItem => prop.ProposalCode)</td>
<td>@Html.DisplayFor(modelItem => prop.Product.Description)</td>
<td>@Html.DisplayFor(modelItem => prop.FinalUnitPrice)</td>
<td>@Html.DisplayFor(modelItem => prop.FinalVolume)</td>
<td>3875.75</td>
<td class="text-center">
<a href="#">
<img src="../../Images/icon_delete.png" width="16" height="16"></a>
</td>
</tr>
}
}
@if (Model.AddedProposal == null)
{
}
</tbody>
</table>
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Received Date:</label>
<div class="col-sm-4">
@Html.TextBoxFor(model => model.ReceivedDate, new { @class = "form-control datepicker", @type = "text" })
</div>
</div>
<div class="form-group">
<label class="col-sm-2 control-label">Remarks:</label>
<div class="col-sm-4">
@Html.TextBoxFor(model => model.Remarks, new { @class = "form-control", @type = "text" })
</div>
</div>
@*</form>*@
</div>
<div class="row col-xs-offset-2" style="padding-top: 30px;">
<button type="submit" class="btn btn-primary">Save</button>
<button type="button" class="btn btn-primary" onclick="window.location='@Url.Action("Index", "Fulfillment")'">Cancel</button>
</div>
}
@使用（Html.BeginForm（“创建”、“采购订单”），
新建{ReturnUrl=ViewBag.ReturnUrl}，
FormMethod.Post，新的{@class=“form horizontal”}）
{
@Html.AntiForgeryToken（）
@Html.ValidationSummary（true）
新采购订单
新采购订单
@**@
@foreach（模型机构中的var inst）
{
机构名称：
@DisplayFor（modelItem=>inst.InstitutionName）
账户分类：
私有的
雇员人数：
50
地址:
克拉克潘潘帕加克拉克自由港区尼诺阿基诺大道1500号
电话号码：
599-3146
}
@**@
@**@
采购订单编号：
@Html.TextBoxFor（model=>model.PurchaseOrderNo，新的{@class=“form control”，@type=“text”}）
购买订单日期：
@Html.TextBoxFor（model=>model.PurchaseOrderDate，新的{@class=“form control datepicker”，@type=“text”}）
提案代码*
描述*
含增值税的单价*
总单位*
总金额（含增值税）*
提议：
@DropDownList（“ProposalID”、新的选择列表（ViewBag.Proposal、“Value”、“Text”）、“SELECT Proposal”、新的{@class=“form control input”、@type=“Text”、@name=“ddlInst”}）
添加
产品：
提案代码
描述
单价增值税
总单位
总金额（含增值税）
行动
@Html.HiddenFor（model=>model.AddedProposal）
@if（Model.AddedProposal！=null）
{
foreach（模型中的var prop.AddedProposal）
{
@Html.HiddenFor(model => model.AddedProposal)
Html.DropDownListFor(m => m.SiteExtendedAttributeValues[0] etc.
Html.DropDownListFor(m => m.SiteExtendedAttributeValues[0].SiteExtendedAttributeDefinitionId
public async Task<ActionResult> Add(string m = null) { }
[HttpPost]
public async Task<ActionResult> Add(FooViewModel m) { }