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Closed 11 years ago.

I am trying this but getting no success

var v=ds.Table[0].AsEnumerable().Where<DataRow>(r=>r.Field<int>("productID")==23);
GridView1.DataSource=v;
GridView1.DataBind();

网格显示,只有1个排向罗尔·哈斯罗尔,但我期望有1个排,有产品信息。

Answer 1

我认为,你应当尝试使用<条码>。表格

ds.Table[0].AsEnumerable().Where<DataRow>(r=>r.Field<int>("productID")==23).CopyToDataTable();

When you convert it to an Enumerable the filtered list has no identifiers for say ProductID hence the grid would fail to map the column and fail.

也可选择使用<条码>AsDataView()而不是<条码>CopyToDataTable(<>>)。

A more detailed explanation can found Binding DataRows

Databinding is controlled by the ListBindingHelper and TypeDescriptor classes. When you bind to a list, the ListBindingHelper.GetListItemProperties method is called to get the columns in the list. If the list implements the ITypedList interface, its GetItemProperties method is called. Otherwise, it will use TypeDescriptor to get the properties of the first item in the list. (this uses reflection)

The DataView class (which DataTable also binds through, using IListSource) implements ITypedList and returns DataColumnPropertyDescriptors that expose the columns in the table. This is why you can bind to a DataView or DataTable and see columns. However, when you bind to a List, there is no ITypedList that can return the columns as properties. It therefore falls back on reflection and shows the physical properties of the DataRow class.

Answer 2

引证。

var results = from myRow in ds.Table[0].Rows 
              where myRow.Field<int>("productID") == 23
              select myRow;

这应该给你看望的几句。

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