Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
378 views
in Technique[技术] by (71.8m points)

asp.net - pass a value into next page

I have login page, once logged in I create a session variable to store the UserName. I've used this variable to retrieve info for this User from Account table with AccountID, name etc and I return the AccountID on the page using a label (lblAccountID).

I have a button to "Add Funds" to this account, which redirects to the AddFunds.aspx page

How can I pass the AccountID into the AddFunds.aspx page which will be used to insert details into Funds table which has the AccountID.

I don't want the AccountID to be visible on the AddFunds.aspx page.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

there are multiple ways to achieve this. i can explain you in brief about the 4 types which we use in our daily programming life cycle.

Please go through the below points.

1 Query String.

FirstForm.aspx.cs

Response.Redirect(“SecondForm.aspx?Parameter=” + TextBox1.Text);

SecondForm.aspx.cs

TextBox1.Text = Request. QueryString["Parameter"].ToString();

This is the most reliable way when you are passing integer kind of value or other short parameters.More advance in this method if you are using any special characters in the value while passing it through query string, you must encode the value before passing it to next page. So our code snippet of will be something like this:

FirstForm.aspx.cs

Response.Redirect(“SecondForm.aspx?Parameter=” + Server.UrlEncode(TextBox1.Text));

SecondForm.aspx.cs

TextBox1.Text = Server.UrlDecode(Request.QueryString["Parameter"].ToString());

2. Passing value through context object

Passing value through context object is another widely used method.

FirstForm.aspx.cs

TextBox1.Text = this.Context.Items["Parameter"].ToString();

SecondForm.aspx.cs

this.Context.Items["Parameter"] = TextBox1.Text;
Server.Transfer(“SecondForm.aspx”, true);

Note that we are navigating to another page using Server.Transfer instead of Response.Redirect.Some of us also use Session object to pass values. In that method, value is store in Session object and then later pulled out from Session object in Second page.

3. Posting form to another page instead of PostBack

Third method of passing value by posting page to another form. Here is the example of that:

FirstForm.aspx.cs

private void Page_Load(object sender, System.EventArgs e)
{
buttonSubmit.Attributes.Add(“onclick”, “return PostPage();”);
}

And we create a javascript function to post the form.

SecondForm.aspx.cs

function PostPage()
{
document.Form1.action = “SecondForm.aspx”;
document.Form1.method = “POST”;
document.Form1.submit();
}
TextBox1.Text = Request.Form["TextBox1"].ToString();

Here we are posting the form to another page instead of itself. You might get viewstate invalid or error in second page using this method. To handle this error is to put EnableViewStateMac=false

4. Another method is by adding PostBackURL property of control for cross page post back

In ASP.NET 2.0, Microsoft has solved this problem by adding PostBackURL property of control for cross page post back. Implementation is a matter of setting one property of control and you are done.

FirstForm.aspx.cs

<asp:Button id=buttonPassValue style=”Z-INDEX: 102″ runat=”server” Text=”Button”         PostBackUrl=”~/SecondForm.aspx”></asp:Button>

SecondForm.aspx.cs

TextBox1.Text = Request.Form["TextBox1"].ToString();

In above example, we are assigning PostBackUrl property of the button we can determine the page to which it will post instead of itself. In next page, we can access all controls of the previous page using Request object.

You can also use PreviousPage class to access controls of previous page instead of using classic Request object.

SecondForm.aspx

TextBox textBoxTemp = (TextBox) PreviousPage.FindControl(“TextBox1″);
TextBox1.Text = textBoxTemp.Text;

As you have noticed, this is also a simple and clean implementation of passing value between pages.

Reference: "How to: Pass Values Between ASP.NET Web Pages"


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...