C # DataSet and DataTable detailed

1. Create a DataSet object:

DataSet ds = new DataSet ("DatasetName");

2. View the structure created by calling Sqldataadapter.fill

Da. Fill (ds, "Orders");

DataTable tbl = ds. TABLE[0];

foreach (DataColumn col in tbl. Columns)

Console.WriteLine (Col. ColumnName);

3, view the data returned by SqlDataAdapter

①, DataRow objects

DataTable tbl = ds. TABLE[0];

DataRow row = tbl. ROW[0];

Console.WriteLine (ros["OrderID"]);

②, checking the data stored in DataRow

DataTable tbl = row. Table;

foreach (DataColumn col in tbl. Columns)

Console.WriteLine (Row[col]);

③, checking for DataRow objects in dattable

foreach (DataRow row in tbl. Rows)

DisplayRow (row);

4, verify the data in the dataset

①, validating DataColumn properties: Readonly,allowdbnull,maxlength,unique

Constrains collection of ②, DataTable objects: Uiqueconstraints,primarykey,foreignkeyconstraints

It is not usually necessary to create a foreignkeyconstraints, because one is created when a relationship is created between the two DataTable objects in the dataset.

③, using Sqldataadapter.fill mode to retrieve schema information