What is Delegate?
Delegate is an important element of C# and is extensively used in every type of .NET application. A delegate is a class whose object (delegate object) can store a set of references to methods.
How do you update a Dataset in ADO.Net and How do you update database through Dataset?
a. Update a dataset;
Dataset ds = new dataset();
SqlDataAdapter adp = new SqlDataAdapter(Query,connection);
Adp.fill(ds);
Again you can add/update Dataset as below
SqlDataAdapter adp1 = new SqlDataAdapter(Query1,connection);
Adp1.fill(ds);
What are the advantages and disadvantages of using datalist?
Adv: the DataList's display is defined via templates,DataList allows for much more customization of the rendered HTML markup , by which it is more user-friendly displays of data.
DisAdv:adding such functionality with the DataList takes more development time than with the DataGrid, as,
1. The Edit/Update/Cancel buttons that can be created in a DataGrid via the EditCommandColumn column type, must be manually added to the DataList, and
2. The DataGrid BoundColumn column types automatically use a TextBox Web control for the editing interface, whereas with the DataList you must explicitly specify the editing interface for the item being edited via the EditItemTemplate.
3. we can't do the paging and sorting with datalist controls.
What is the difference between data reader and data adapter?
DateReader is an forward only and read only cursor type if you are accessing data through DataRead it shows the data on the web form/control but you can not perform the paging feature on that record(because it's forward only type). Reader is best fit to show the Data (where no need to work on data)
DataAdapter is not only connect with the Databse(through Command object) it provide four types of command (InsertCommand, UpdateCommand, DeleteCommand, SelectCommand), It supports to the disconnected Architecture of .NET show we can populate the records to the DataSet. where as Dataadapter is best fit to work on data.
What is the difference between data reader and data set?
1) DataSet is disconnected object type. It uses XML to store data.
2) It fetches all data from the data source at a time
3) Modifications can be updated to the actual database
4) It will reduce the application performance.
Does SQLClient and OLEdb class share the same functionality?
No, each have its own functionality,
ex : for sql client , there is SqlConnection object
and for oledb client , there is OleDBConnection
Why edit is not possible in repeater?
It has no such feature.
b. Update database through dataset.
SqlCommandBuilder mySqlCommandBuilder = new SqlCommandBuilder(mySqlDataAdapter);
Foreach(datarow dr in ds.table[0].rows)
{
Dr[“column Name”] = “value”;
mySqlDataAdapter.Update(ds);
}
What are the steps to connect to a database?
1. Create a connection. This requires a connection string, which can be given declaratively or put in a well defined place like the .config files. Advantage of keeping in .config files is that it enables use of Connection Pooling by .Net framework, else even one small change in connection string will cause CLR to think it's not the same connection and will instantiate new connection for other request.
2. Open the connection and keep it open until done, typically done as using (con) { //use }
3. If using connected data model, create a SqlCommand object, decorate it with desired command, command type (stored procedure for eg), add any parameters and their values to the command, and then consume the command by using ExcuteReader or ExecuteScalar. In case of ExecuteReader, we will get back a handle to a fast-forward, read only pointer to the recordset. We can also decorate Command object with multiple recordsets in 2.0 and execute one by one (MARS - Multiple Active Record Sets)
4. If using disconnected data model, create a DataAdapter object, decorate it with desired SELECT, INSERT, UPDATE, DELETE commands, add parameters as necessary and then fill up a DataSet or DataTable using the DataAdapter. Subsequent SQL can be executed using insert, update, delete commands on the dataset.
How do you connect to SQL Server Database without using sqlclient?
you can connect sql using oledbname space .
What is Partial class?
A Partial class is a class that can be split into two or more classes. This means that a class can be physically separated into other parts of the class within the same namespace. All the parts must use the partial keyword. All the other classes should also have the same access modifier. At the compile time, all the partial classes will be treated as a single class. Let us list some advantages of having partial classes.
good.........
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