重拾ASP.NET頁面間傳值

1.Use Query String

註：以前總是忽略了Server.UrlEncode()  AND Server.UrlDecode() 切記，切記！

(1)Source Page

1 protected void QueryStringButton_Click(object sender, EventArgs e)
2         {
3             Response.Redirect("QueryStringPage.aspx?Data=" + Server.UrlEncode(DataToSendTextBox.Text));
4         }

(2)Target Page

1  <form id="form1" runat="server">
2     <div>
3         <h1>Target Page - Query String</h1>
4         The data received from the source page is: <%=Server.UrlDecode(Request.QueryString["Data"]) %><br /><br />
5     </div>
7     </form>

2.Use Session

(1)Source Page

 

1  protected void SessionStateButton_Click(object sender, EventArgs e)
2         {
3             Session["Data"] = DataToSendTextBox.Text;
4             Response.Redirect("SessionStatePage.aspx");
5         }

(2)Target page

 

 <div>
        <h1>Target Page - Session State</h1>
        The data received from the source page is: <%=Session["Data"] %><br /><br />
    </div>
    </form>

3.Use HttpPost

說明：印象中這是第一次見到這種用法，這次該記住了。

(1)Source Page

 <asp:Button ID="HttpPostButton" runat="server" Text="Use HttpPost" 
            PostBackUrl="~/HttpPostPage.aspx"/><br /><br />

(2)Target page

<h1>Target Page - HttpPost</h1>
        The data received from the source page is: <%=Request.Form["DataToSendTextBox"] %><br /><br />
<fieldset>
<legend>All form data from the sending page</legend>
<asp:Label ID="ReceivedDataLabel" runat="server" Text="Label"></asp:Label>
</fieldset>
<br />

 

  protected void Page_Load(object sender, EventArgs e)
        {
            System.Text.StringBuilder displayValues =
new System.Text.StringBuilder();
            System.Collections.Specialized.NameValueCollection
                postedValues = Request.Form;
            String nextKey;
for (int i = 0; i < postedValues.AllKeys.Length; i++)
            {
                nextKey = postedValues.AllKeys[i];
if (nextKey.Substring(0, 2) != "__")
                {
                    displayValues.Append("<br>");
                    displayValues.Append(nextKey);
                    displayValues.Append(" = ");
                    displayValues.Append(postedValues[i]);
                }
            }
            ReceivedDataLabel.Text = displayValues.ToString();

        }

4.Use Public Properties

(1)Source Page

 說明：這個方法也是很少用，不過在某些時候還是用得到的。

 public string DataToSend
        {
get
            {
return DataToSendTextBox.Text;
            }
        }

protected void PublicPropertiesButton_Click(object sender, EventArgs e)
        {
            Server.Transfer("PublicPropertiesPage.aspx");
        }

(2)target page

 

<div>
<h1>Target Page - Public Properties</h1>
        The data received from the source page is: <%=PreviousPage.DataToSend %><br /><br />
<asp:hyperlink ID="Hyperlink1" runat="server" NavigateUrl="~/Default.aspx">Return to Source Page</asp:hyperlink>
</div>

5.Use Control Infomation

(1)Source Page

 說明：以前只有在應用主版頁面時才去FindControl(),長眼見了。

<asp:TextBox ID="DataToSendTextBox" runat="server" Text="Hello World!"></asp:TextBox><br /><br />

 protected void ControlInfoButton_Click(object sender, EventArgs e)
        {
            Server.Transfer("ControlInfoPage.aspx");
        }

(2)Target page

 

<h1>Target Page - Control Info</h1>
        The data received from the source page is: 
<asp:Label ID="DataReceivedLabel" runat="server" Text="Label"></asp:Label><br /><br />

 

protected void Page_Load(object sender, EventArgs e)
        {
var textbox = PreviousPage.FindControl("DataToSendTextbox") as TextBox;
if (textbox != null)
            {
                DataReceivedLabel.Text = textbox.Text;
            }

        }

反思：似乎作者沒有把Cookies放到這一類來，why？