What is partial classess in .net?

When there is a need to keep the business logic separate from the User Interface or when there is some class which is big enough to have multiple number of developers implement the methods in it, the class can be separated and written in different files as partial class.

The keyword partial must appear in each class.

//syntax for C#
Public partial class MyPartialClass1
{
//code
}

// this code could be in file1

Public partial class MyPartialClass1
{
//code
}
// this code could be in file2

Explain how to pass a querystring from an .asp page to aspx page.

Consider the following URL:

http:// localhost/form.aspx?param1=career&param2=ride

This html addresses use QueryString property to pass values between pages.

From the URL above the information obtained is:

form.aspx: which is the destination page for your browser.
Param1 is the first parameter, the value of which is set to career
Param2 is the first parameter, the value of which is set to ride

The ‘?’ marks the beginning of the QueryString
‘&’ is used as a separator between parameters.

private void formButtonSubmit_Click(object sender, System.EventArgs e)
{
Response.Redirect("form.aspx?Param1=" +
this.formTextfieldParam1.Text + "&Param2=" +
this. formTextfieldParam2.Text);
}

The above code is a submit button event handler and it sends the values of the query string to the second page.

The following code demonstrates how to retrieve these valus on the second page:
private void Page_Load(object sender, System.EventArgs e)
{
this.form2TextField1.Text = Request.QueryString["Param1"];
this. form2TextField2.Text = Request.QueryString["Param2"];
}

You can also use the following method to retrieve the parameters in the string:

for (int i =0;i < Request.QueryString.Count;i++)
{
Response.Write(Request.QueryString[i]);
}