Question

我有一个从xml文件填充的DataSet，我想将主DataTable拆分成几个DataTable。

假设这是表的格式：

Column1 | Column2
1234    | 4567
1234    | 1122
1234    | 2233
1000    | 3344
1000    | 5566

我需要将上面的内容拆分为2个表，一个包含所有1234个值，另一个包含1000个值。

这是我阅读xml文件并正常工作的方式：

WebClient wc = new WebClient();
            wc.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
            string strXmlString = wc.DownloadString(strUrl); // Download the URL to a string
            strXmlString = Regex.Replace(strXmlString, @"m:null.+?>{1}", @"/>"); // Find ' m:null[anything]>' and replace it with '/>'
            strXmlString = Regex.Replace(strXmlString, @"[\s]{1}m:.+?>{1}", @">"); // Find ' m:type[anything]>' and replace it with '>'
            XmlDocument xDoc = new XmlDocument();
            xDoc.LoadXml(strXmlString); // Load the XML String into an XML Doc
            XmlReader xReader = new XmlNodeReader(xDoc);
            DataSet ds = new DataSet();
            ds.ReadXml(xReader); // Upload the XML Doc Data to the DataSet

如何将ds.Tables[0]拆分为2个表？

Answer 1

您可以使用Linq和especiall Enumerable.GroupBy：

var column1Groups = ds.Tables[0].AsEnumerable()
    .GroupBy(r => r.Field<string>("Column1"));
foreach(var group in column1Groups)
{
    // if you need only the 1234  and 1000 groups:
    if(group.Key == "1000" || group.Key == "1234")
    {
        ds.Tables.Add(group.CopyToDataTable());
    }
}

与几乎纯粹的Linq相同：

var valuesNeeded = new[]{ "1000", "1234" };
var newTables = ds.Tables[0].AsEnumerable()
    .GroupBy(r => r.Field<string>("Column1"))
    .Where(g => valuesNeeded.Contains(g.Key))
    .Select(g => g.CopyToDataTable())
    .ToArray();
ds.Tables.Clear(); // if you need to clear it first
ds.Tables.AddRange( newTables );

Answer 2

DataTable dt1  = ds.Tables[0].Select("Column1 ='1000'").CopyToDataTable();
DataTable dt2 = ds.Tables[0].Select("Column1 ='1234'").CopyToDataTable();

asp.net拆分xml DataTable

2 个答案: