Programming Tutorials

Using DataTable AcceptChanges() Method The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we use the DataTable class AcceptChanges() method in an asp.net web application. The DataTable class AcceptChanges() method commits all the changes made to this table since the last time AcceptChanges() method was called. So the developers use the AcceptChanges() method to commit the changes they made on a DataTable instance. When the asp.net web developers ...

DataRow ItemArray Property .NET framework's DataRow class represents a row of data in a DataTable. DataRow class exists in the System.Data namespace. DataRow class’s ItemArray property allows us to get or set all the values for this row through an Array. ItemArray property value type is System.Object[] which represents an Array of type Object. If we use the ItemArray property to set a row value, the Array must have the same size and order as the DataTable's column collection. Passing null in ItemArray indicates that no value was specified. DataRow ItemArray property throws an ArgumentException exception if the Array is larger than the table columns number. It throws InvalidCastException if a value in the Array does not match its DataType in its respective DataColumn. The property throws ConstraintException if an edit broke a constraint. It throws ReadOnlyException if an edit tried to change the value of a read-only column. ...

Select rows from a DataTable The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we can select rows from a DataTable instance. So we will get all the rows from a DataTable. The DataTable class Select() method gets an array of DataRow objects. The DataTable Select() method returns an array of DataRow objects. The asp.net web developers don’t have to pass any parameter to this Select() method to get all the rows from a DataTable object. UsingDataTableSel...

Select rows that match filter criteria from a DataTable The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we can select data from a DataTable instance with the specified condition. So we will get the rows from the DataTable which match the filter criteria. The DataTable class Select() method gets an array of DataRow objects. The Select(String) method overload gets an array of all DataRow objects that match the filter criteria. The Select(string?...

Count rows in a DataTable The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we can count rows in a DataTable. So we have to count the DataRow objects within a DataTable instance. Here we used the DataTable class Rows property to get its rows collection as a DataRowCollection object. Then we used DataRowCollection’s Count property to count the rows within the rows collections. The DataTable class Rows property gets the collection of rows that belong to th...

Delete a row from the DataTable The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we can delete a row from a DataTable. So we will remove a DataRow object from a DataTable instance at the specified index position. In this example code, we will remove a row by using its index value from a DataTable object. Here we used the DataTable class Rows property to get its rows collection as a DataRowCollection object. Then we used DataRowCollection’s RemoveAt() me...

Insert a new row into the DataTable The DataTable class represents one table of in-memory data. The DataTable objects are conditionally case-sensitive. To create a DataTable programmatically the asp.net developers must first define its schema by adding DataColumn objects to the DataColumnCollection. To add rows to a DataTable, the developers must use the NewRow() method to return a new DataRow object at first. The DataTable also contains a collection of Constraint objects that can be used to ensure the integrity of the data. The following asp.net c# tutorial code demonstrates how we can insert a new row into a DataTable. So we have to insert a new DataRow object into the DataTable’s specified index position. Here we used the DataTable class Rows property to get its rows collection as a DataRowCollection object. Then we used DataRowCollection’s InsertAt() method to insert a new DataRow object at a specified index position of the rows collection...