GetSchemaTable Columns Missing?
I am using this code to get data from a dataReader into a DataTable which ca开发者_Python百科n then be serialised.
However, it looks like any column with a null value isnt being written to the xml.
I cant see the issue.
This is my entire class, and im calling this method
Process(IDataReader data, string filePath)
Im certain that this works, because i have used it to serialise dataTables before
Process(DataTable table, string filePath)
So i think it must be in the "GetDataTableFromSqlDataReader" method??
public class DataSerialisation
{
public static DataRow GetFirstDataRow(string xmlFilePath)
{
return GetDataTable(xmlFilePath).Rows[0];
}
public static DataTable GetDataTable(string xmlFilePath)
{
DataSet ds = new DataSet();
ds.ReadXml(xmlFilePath);
return ds.Tables[0];
}
private static DataTable GetDataTableFromSqlDataReader(IDataReader dr)
{
DataTable dtSchema = dr.GetSchemaTable();
DataTable dt = new DataTable();
ArrayList listCols = new ArrayList();
if (dtSchema != null)
{
foreach (DataRow drow in dtSchema.Rows)
{
string columnName = Convert.ToString(drow["columnName"]); //drow["columnName"].ToString();
DataColumn column = new DataColumn(columnName, (Type) (drow["DataType"]));
//column.ColumnName = columnName;
//column.Unique = (bool) (drow["IsUnique"]);
column.AllowDBNull = (bool) (drow["AllowDBNull"]);
//column.AutoIncrement = (bool) (drow["IsAutoIncrement"]);
//column.AutoIncrement = (bool) (drow["IsAutoIncrement"]);
listCols.Add(column);
dt.Columns.Add(column);
}
while (dr.Read())
{
DataRow dataRow = dt.NewRow();
for (int i = 0; i < listCols.Count; i++)
dataRow[((DataColumn) listCols[i])] = dr[i];
dt.Rows.Add(dataRow);
}
}
return dt;
}
public static void Process(IDataReader data, string filePath)
{
Process(GetDataTableFromSqlDataReader(data), filePath);
}
public static void Process(DataTable table, string filePath)
{
DataSet ds = new DataSet();
ds.Tables.Add(table.Clone());
foreach (DataRow row in table.Rows)
{
DataRow newRow = ds.Tables[0].NewRow();
for (int col = 0; col < ds.Tables[0].Columns.Count; col++)
newRow[col] = row[col];
ds.Tables[0].Rows.Add(newRow);
}
ds.WriteXml(new StreamWriter(filePath));
}
}
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