数据表上的LINQ查询

我试图在数据表对象上执行LINQ查询，奇怪的是，我发现在数据表上执行这样的查询并不简单。例如:

var results = from myRow in myDataTable
where results.Field("RowNo") == 1
select results;

这是不允许的。我怎么才能让这样的东西工作呢?

我很惊讶，LINQ查询不允许在数据表上!

当前回答

试试这个

var row = (from result in dt.AsEnumerable().OrderBy( result => Guid.NewGuid()) select result).Take(3) ;

2012-05-18 07:15:08

其他回答

//Create DataTable 
DataTable dt= new DataTable();
dt.Columns.AddRange(new DataColumn[]
{
   new DataColumn("ID",typeof(System.Int32)),
   new DataColumn("Name",typeof(System.String))

});

//Fill with data

dt.Rows.Add(new Object[]{1,"Test1"});
dt.Rows.Add(new Object[]{2,"Test2"});

//Now  Query DataTable with linq
//To work with linq it should required our source implement IEnumerable interface.
//But DataTable not Implement IEnumerable interface
//So we call DataTable Extension method  i.e AsEnumerable() this will return EnumerableRowCollection<DataRow>


// Now Query DataTable to find Row whoes ID=1

DataRow drow = dt.AsEnumerable().Where(p=>p.Field<Int32>(0)==1).FirstOrDefault();
 //

2012-01-05 08:43:15

试试这个

var row = (from result in dt.AsEnumerable().OrderBy( result => Guid.NewGuid()) select result).Take(3) ;

2012-05-18 07:15:08

正如@ch00k所说:

using System.Data; //needed for the extension methods to work

...

var results = 
    from myRow in myDataTable.Rows 
    where myRow.Field<int>("RowNo") == 1 
    select myRow; //select the thing you want, not the collection

您还需要向System.Data.DataSetExtensions添加一个项目引用

2008-08-14 11:07:52

VB。代码如下所示:

Dim results = From myRow In myDataTable  
Where myRow.Field(Of Int32)("RowNo") = 1 Select myRow

2012-10-17 16:04:52

你可以对Rows集合上的对象使用LINQ，如下所示:

var results = from myRow in myDataTable.Rows where myRow.Field("RowNo") == 1 select myRow;

2008-08-14 10:11:08

数据表上的LINQ查询

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