1. NameValueCollectionValueProvider:
ValueProvider 的数据容器一般具有类似字典的结构。NameValueCollection 表示一种 key 和value 均为字符的字典。
方法 GetKeysFromPrefix 以字典的形式返回数据源容器中所有具有指定前缀的key。
两种前缀的形式:
两种前缀形式辅助实现Model绑定数据。
一种是采用"." 一种是采用"[]" 集合的方式：
public ActionResult Index()
{
NameValueCollection datasource = new NameValueCollection();
datasource.Add("foo.Name", "Foo");
datasource.Add("foo.PhoneNo", "123456789");
datasource.Add("foo.EmailAddress", "[email protected]");
datasource.Add("foo.Address.Province", "江苏");
datasource.Add("foo.Address.City", "苏州");
datasource.Add("foo.Address.District", "工业园区");
datasource.Add("foo.Address.Street", "星湖街328号");
NameValueCollectionValueProvider valueProvider = new NameValueCollectionValueProvider(datasource, CultureInfo.InvariantCulture);
return View(valueProvider);
}
@model NameValueCollectionValueProvider
<html>
<head>
<title>指定前缀的Key</title>
<link rel="stylesheet" href="~/Style.css" />
</head>
<body>
<table rules="all">
<tr><th colspan="2">foo</th></tr>
@foreach (var item in Model.GetKeysFromPrefix("foo"))
{
<tr><td>@item.Key</td><td>@item.Value</td></tr>
}
<tr><th colspan="2">foo.Address</th></tr>
@foreach (var item in Model.GetKeysFromPrefix("foo.Address"))
{
<tr><td>@item.Key</td><td>@item.Value</td></tr>
}
</table>
</body>
</html>
现在来看看数组"[]"形式的代码：
public ActionResult Index()
{
NameValueCollection datasource = new NameValueCollection();
datasource.Add("first[0].Name", "Foo");
datasource.Add("first[0].PhoneNo", "123456789");
datasource.Add("first[0].EmailAddress", "[email protected]");
datasource.Add("first[1].Name", "Bar");
datasource.Add("first[1].PhoneNo", "987654321");
datasource.Add("first[1].EmailAddress", "[email protected]");
NameValueCollectionValueProvider valueProvider = new NameValueCollectionValueProvider(datasource, CultureInfo.InvariantCulture);
return View(valueProvider);
}
@model NameValueCollectionValueProvider
<html>
<head>
<title>指定前缀的Key</title>
<link rel="stylesheet" href="~/Style.css" />
</head>
<body>
<table>
<tr><th colspan="2">first</th></tr>
@foreach (var item in Model.GetKeysFromPrefix("first"))
{
<tr><td>@item.Key</td><td>@item.Value</td></tr>
}
<tr><th colspan="2">first[0]</th></tr>
@foreach (var item in Model.GetKeysFromPrefix("first[0]"))
{
<tr><td>@item.Key</td><td>@item.Value</td></tr>
}
<tr><th colspan="2">first[1]</th></tr>
@foreach (var item in Model.GetKeysFromPrefix("first[1]"))
{
<tr><td>@item.Key</td><td>@item.Value</td></tr>
}
</table>
</body>
</html>
2. DictionaryValueProvider: 是将数据源存放在真正的字典对象之中。他们之间不同之处在于NameValueCollection 中的元素仅局限于字符串。
public ActionResult DataOfChildActionValueProvider()
{
ControllerContext.RouteData.Values["Foo"] = "abc";
ControllerContext.RouteData.Values["Bar"] = "ijk";
ControllerContext.RouteData.Values["Baz"] = "xyz";
ChildActionValueProvider valueProvider = new ChildActionValueProvider(ControllerContext);
return View(valueProvider);
}
@model ChildActionValueProvider
<table rules="all">
<tr>
<th>Key</th><th colspan="2">Value</th>
</tr>
@{
var dictionary1 = this.Model.GetDataSource();
}
@foreach (var item1 in dictionary1)
{
DictionaryValueProvider<object> valueProvider = item1.Value.RawValue as DictionaryValueProvider<object>;
if (null == valueProvider)
{
<tr>
<td>@item1.Key</td><td colspan="2">@item1.Value.RawValue</td>
</tr>
}
else
{
var dictionary2 = valueProvider.GetDataSource();
<tr>
<td rowspan="@(dictionary2.Count + 1)">@item1.Key</td>
<th>Key</th><th>Value</th>
</tr>
foreach(var item2 in dictionary2)
{
<tr><td>@item2.Key</td><td>@item2.Value.RawValue</td></tr>
}
}
}
</table>
同时在Index 中
<html>
<head>
<title>ChildActionValueProvider的数据结构</title>
<link rel="stylesheet" href="~/Style.css" />
</head>
<body>
@Html.Action("DataOfChildActionValueProvider", new { Foo = 123, Bar = 456, Baz = 789 })
</body>
</html>
时间： 2024-12-19 09:49:06