• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Ado Presentation
 

Ado Presentation

on

  • 245 views

screen shots and instructions for reading data and rendering to a .net web page

screen shots and instructions for reading data and rendering to a .net web page

Statistics

Views

Total Views
245
Views on SlideShare
245
Embed Views
0

Actions

Likes
0
Downloads
4
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as OpenOffice

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Ado Presentation Ado Presentation Presentation Transcript

    • Create Database
      • Open a new web site in Visual Studio
      • Right click on add new item
      • Choose Database
      • Make a SQL database named “MyDatabase.mdf”
    • Database Explorer
      • Creating a database takes you from Solution Explorer to Database Explorer
      • You should see your database “MyDatabase.mdf”
    • Create a New Table
      • Drill down under MyDatabase
      • Right click on Tables and Add new table
    • Enter fields into table
      • Enter a field and name it ”my_varchar” and make it type varchar(50)
      • Enter a field name “my_int” and make it type int – make the int an identity field so that it can auto increment and server as a key
    • Save Table
      • Save table and name it “my_tableve table and name it “my_table ”
    • Open Table to add data to it
      • Right click on table and select 'Show table data'
    • Enter data into table
      • Enter at least 2 rows of data
      • Enter a string in the 'my_varchar' field
      • You won't need to, nor be allowed to enter data into the my_int field if you set it up as identity because it will auto fill
    • Get Connect String
      • Right click on Database name
      • Click on properties
      • See connection string in lower left properties
    • ConnectionString extract from Properties
      • You should be able to select the connect string and copy it to the buffer
      • See next slide for what it should look like when you put it in the code
    • Connect String You need to modify the connect string that you extract from the properties of the Database so that the compiler will accept it. Here is a sample connect string: Data Source=.QLEXPRESS; AttachDbFilename=|DataDirectory| MyDatabase.mdf;Integrated Security=True;User Instance=True;
    • Create Web Form
      • Go back to Solution Explorer
      • Right click on the website name and add new item
      • Add a web form names AdoTest.aspx
      • Indicate that it is using code behind
    • AdoTest.aspx.cs
      • Code behind helps to separate the code from the front end (html and controls)
      • We'll code the database read and data rendering in the code behind
      • We'll put cod in Page_Load method
    • Code SqlConnection
      • Create a string containing the data connect string that we discussed above
      • Create a Sql Connection using the string
      • Note the red squigly line under SqlConnection
    • Add the “using ...” to Reference .net library
      • If you right click on the red squiggly you can choose to resolve the problem by insering a “using” clause to the top of the code page
      • Correct this error and remove the red line
    • Add the SqlCommand
      • Code a SqlCommand by combining a sql string with a connection
      • To select the data we created in the database use this sql:
      • Select my_varchar,my_int from my_table
    • Open the connection
      • Before you can execute a command or work you must open a connection
      • Open connections are like open pipes to the database – you will need to close it when you are done
    • Execute Command and Get a Reader back
      • Enter the code to execute the command a return an instance of a SqlDataReader
    • Render the data to the web form with HTML
      • You can use the Reponse.Write method to write data directly to the browser
      • See comments in code on the next slide as to how data is extracted form the reader
    • Extracting Data from a SqlDataReader When you extract data from a reader, you should be aware of the data type you are extracting and how it maps to the language (.net) data types
    • Code to iterate through a reader while (reader.Read()) { //my_varchar is varchar which maps to .net string so use GetString string name = reader.GetString(0); //my_int is int which maps to Int32 Int32 id = reader.GetInt32(1); //now that I have loaded the data into c# string I can output //here I'm using response.write to output directly to the //browser. //I concatenate the data with html to produce the 'layout' //I want Response.Write(name + &quot; &quot; + id + &quot;<br />&quot;); }
    • Close connection
      • After you have finished with the reader and the database connection you need to close it
      • If you don't close the connection you will run into problems with the database – it will think you are still connected
    • View Web page in browser
      • You can view you web page in the browser
      • This will force your code to compile and bring up a browser window with the response
      • To do this right click on the .aspx file in the solution explorer and choose to 'View in Broswer'
    • Simple Output
      • In my first bit of code I just output the data with an HTML break to see that my code is compiling and reading from the database
    • Write a Table
      • In the next bit of code I render the data in an html table
      • This table can be styled if needed
    • Tabular Output
      • View the data rendered as a table