view image in a non-Project folder - asp.net

I upload an image to my server in a folder Called Updates. Than I'm trying to view this pic by using the following:
<asp:Image runat="server" ImageUrl="C:/Uploads/ec.jpg" />
Basically ec.jpg is in a folder called Uploads which is in C:. When I run my web app the pic doesn't show.
Now if I put the image in my actual Project file and than I try viewing it, it shows just fine.

OK, so my answer above is valid if you just want to point to the image via ImageUrl. You can use a handler to access the image outside of your app path though. This is an example handler:
<%# WebHandler Language="C#" Class="Handler" %>
using System;
using System.Web;
public class Handler : IHttpHandler {
public void ProcessRequest (HttpContext context) {
HttpResponse r = context.Response;
r.ContentType = "image/png";
string file = context.Request.QueryString["file"];
r.WriteFile(file);
}
public bool IsReusable {
get {
return false;
}
}
}
Create a a Generic Handler, use the above code. If you created it with the file name of Image.ashx in the root of you application you would then:
<asp:Image runat="server" ImageUrl="~/Image.ashx?file=C:/Uploads/ec.jpg"/>
This Is NOT Production Quality Code
as there are no safeguards and this handler would return any file from the hard disk!

#justin808 is Right..
Add ImageFolder on your Solution.
And then use
<asp:Image runat="server" ImageUrl="~/ImageFolder/ec.jpg"/>
By simply draging your image on your designer.
Regards

ImageUrl is a relative or absolute URL to your image. Your image must be within the web application's hierarchy or it won't be accessible by your application

Related

Master property is not auto generated in aspx designer causing runtime errors

I have a content page that uses a MasterPageFile, and in the code we try to access a master property Master.SessionId.
<%# Page Title="" Language="C#" MasterPageFile="~/Admin/AdminFrontend.Master" AutoEventWireup="true"
CodeBehind="Reasons.aspx.cs" Inherits="Admin.Other.Reasons" %>
<asp:Content ID="Content2" ContentPlaceHolderID="cphMainBody" runat="server">
<reason session-id="<%=Master.SessionId%>">
</reason>
</asp:Content>
But the Master.SessionId is not recognized, Master is not referring to the correct master file. Similar code works on another file within the project. The only notable difference that we found is that the page that works has the following auto-generated code in the aspx.designer.cs file.
public partial class MyChart {
/// <summary>
/// Master property.
/// </summary>
/// <remarks>
/// Auto-generated property.
/// </remarks>
public new Admin.AdminFrontend Master {
get {
return ((Admin.AdminFrontend)(base.Master));
}
}
}
This is the designer for my Reasons.aspx file.
//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool.
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
namespace Admin.Other
{
public partial class Reasons
{
}
}
I am not sure what is the problem, why in one file that property is auto-generated and not in the other. I thought Visual Studio is doing something crazy. I restarted VS2019 and also tried restarting my machine. Both didn't solve the
problem.
There may not even 'be' a Designer page for the "Reasons.aspx.cs". Please check to ensure it exists for the Reasons.aspx page (open the Solution Explorer and view the associated to the Reason.aspx file). If the Designer file does not exist, select/highlight the Reason.aspx file in the Solution Explorer, then use the upper menu bar (in Visual Studio), and choose the Project > Convert to Web Application selection. If that selection is missing from the Projects pulldown menu, this typically indicates all Designer files are connected to your CodeBehind files.
If you do have a Reasons.aspx.designer.cs, please provide the code here so we can compare it to the one from your MyChart example.
At your Reasons.aspx.cs file,
you can add public property and return the Master.sessionID.
For example;
public partial class MyChart
{
public string MySession
{
get
{
return Master.SessionID;
}
}
}
At your aspx file, use
<reason session-id="<%=MySession%>"></reason>

Using ASP.NET Server Controls in MVC?

On my current project I need to add a functionality that allows the user to view a thumbnail of their uploaded PDF. I've found a handy component that achieves this (the basic version is free, but it's enough for my current needs). Anyways, the control is pretty outdated (2010), therefore there doesn't seem to be MVC support. On the demos they depict usage of the control as such:
The View's Markup:
<form method="post" runat="server" enctype="multipart/form-data">
<asp:Panel ID="thumbnailsPanel" runat="server" />
</form>
The thumbnail control is instantiated via code, the byte array which represents the thumbnail is passed to the control and the control is added to thumbnailsPanel
<script runat="server">
protected void DisplayThumbs_Click( object sender, System.EventArgs e )
{
Thumbnail thumbnail = new Thumbnail();
thumbnail.SessionKey = sessionID;
thumbnail.Index = i;
thumbnailsPanel.Controls.Add( thumbnail );
}
</script>
Given that I can't declare a Thumbnail control in my razor view, how would I used this control in MVC? I've spent a few hours trying to make this control MVC friendly to no avail, the best I've come up with is to include a .ASPX view (not.cshtml) in my project and render the Thumbnail control on that view. Obviously this is not desirable.
So how would you go about using a ASPX server controls in MVC? Is the idea a bad one altogether and should not be practised?
I worked around it in a project of mine by reimplementing the control as a HtmlHelper. Assuming the control isn't too complicated then it should work for you too. Do this:
Dump the Control's source using Reflector
Massage the source so it actually compiles (as source from Reflector doesn't usually compile straight away)
Identify what state the control has. Convert the state from member properties into members of its own new ViewModel class.
Find the Render method and convert it to a HtmlHelper that uses ViewContext.Writer
For example:
public class FooControl : Control {
public String Message { get; set; }
public override void Render(HtmlTextWriter wtr) {
wtr.WriteLine("<p>");
wtr.WriteLine( message );
wtr.WriteLine("</p>");
}
}
Becomes this:
public class FooViewModel {
public String Message { get; set; }
}
// This method should exist in a static Extensions class for HtmlHelper
public static void Foo(this HtmlHelper html, FooViewModel model) {
HtmlTextWriter wtr = html.ViewContext.Writer;
wtr.WriteLine("<p>");
wtr.WriteLine( model.Message );
wtr.WriteLine("</p>");
}

Recommendations for good ways to display user messages in asp.net?

I have an app full of pages and user controls, many of which have one or more label controls on them for displaying various different messages to the user.
Example: the AddCompany.ascx user control, normally used on the Company.aspx page (with App.Master MasterPage) has a label on it called "OutOfCreditLabel" with Text="Error: You cannot create a new company, as you are out of credit". The code checks the credit and shows the label if needed.
I want to get rid of all these labels all over the place and just have a method I can call from anywhere like
ShowUserMessage("Text goes here");
In previous projects I've implemented this as a single label on the master page and public method in the .master.cs - as long as the page has the line
<%# MasterType VirtualPath="~/App.master" %>
in it, this works - but I can't get it to work on user controls (.ascx.cs). Is there a trick to this?
Or... Is there a better way?
What would you recommend for a "global" user message method that works from anywhere in the site?
Any nice jQuery solutions, perhaps?
Update
RPM1984 has asked for further clarification, so I'm trying to ask this a different way:
I need a method I can call from the code-behind (of a page or a user control) which will then display whatever text I specify to the user, like how stackoverflow tells you about new answers to your question when you next visit the site. It can be up the top of the window (like SO) or somewhere on the page, doesn't matter. What matters is that it's a "global" approach, rather than having various javascript alerts and asp:label's littered over every other page and user control in the project.
Something like this scenario:
A user clicks the "Create Widget" button on my "widget manager" user control on my page. In the event handler is:
if (User.IsOutOfCredit)
{
ShowUserMessage("Sorry, you cannot create widgets; you are out of credit.");
}
This results in the user seeing "Sorry, you cannot create widgets; you are out of credit." Either in a pop-up or red text in the page somewhere or at the top like StackOverflow, anything is fine
Does that make sense?
Why not a simple HTML "old-school" extension method? (i.e static method)
namespace Web.Helpers
{
public class HtmlHelpers
{
public static string Label(string target)
{
var dynamicText = SomeWhere.GetSomeCoolText();
return String.Format("<label for='{0}'>{1}</label>", target, dynamicText);
}
}
}
Then in your HTML:
<%= HtmlHelpers.Label("sometarget") =>
In your main master page, just import the namespace:
<%# Import Namespace="Web.Helpers" %>
EDIT after question updated
Ok, i see what you're trying to do now. I would recommend doing it all client-side.
That is, in your main master page, create an initially hidden <div> with a unique id:
<div id="message" style="display: none"></div>
Then create a helper method somewhere in your web project, rendering out some script.
public void DisplayMessage()
{
string message = SomeWhere.GetSomeCoolText();
StringBuilder script = new StringBuilder();
script.AppendFormat("$('message').show().append("<span>{0}</span>")", message);
Page.ClientScript.RegisterClientScriptBlock(this.GetType(), script.ToString(), true);
}
Of course, this is just a guideline. You dont have to use jQuery, you don't have to hardcode the script in the method. You could create a JavaScript function that accepts a string and modifies the HTML of the div, then just call the function.
It all depends on how complicated your "message" is, if you need special server controls, internationalization, etc.
But this is certainly the easiest way to accomplish what you want (IMHO).
Personally, I'd prefer using the HttpContext.Current.Items dictionary with a custom control. Similar to Keith Bluestone's approach, but doesn't require an arbitrarily named control on the page; it makes it very clear what's going on. You could package it into one class as a server control easily enough, but here it is to drop into a standard web project.
To register a message in your code behind:
SiteMessageUtility.Add("Test message");
To display in your page, or master page, or wherever, really:
<%# Register TagPrefix="custom" TagName="SiteMessage" Src="~/Controls/SiteMessage.ascx" %>
<custom:SiteMessage runat="server" />
Here's the files you'll need:
~\App_Code\SiteMessageUtility.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
public static class SiteMessageUtility
{
public static void Add(string message)
{
string currMessage = HttpContext.Current.Items["message"] as string;
if (currMessage == null)
{
HttpContext.Current.Items["message"] = message;
}
else
{
HttpContext.Current.Items["message"] = currMessage + "<br/>" + message;
}
}
}
~\Controls\SiteMessage.aspx
<%# Control Language="C#" AutoEventWireup="true" CodeFile="SiteMessage.ascx.cs" Inherits="Controls_SiteMessage" %>
<asp:Literal runat="server" ID="message" />
~\Controls\SiteMessage.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Controls_SiteMessage : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected override void OnPreRender(EventArgs e)
{
message.Text = (string)HttpContext.Current.Items["message"];
base.OnPreRender(e);
}
}
On the master page add the following controls:
the hfMsg hidden field will hold the message that will be displayed
and the hfCtrl will hold the name of the html control that will display this message which will be in this example lblMsg.
<label id="lblMsg" style="background-color:Yellow; border:solid 1px; width:200px;height:100px;display:none;"></label>
<asp:HiddenField ID="hfMsg" runat="server" />
<asp:HiddenField ID="hfCtrl" runat="server" />
NOTE:you can add another html control with a different id on an ASCX control and use it to display the message instead of the lblMsg.
and the following script:
<script language="javascript" type="text/javascript">
var msg = $('#<%= hfMsg.ClientID %>').attr("value");
var ctrl = $('#<%= hfCtrl.ClientID %>').attr("value");
if (msg != undefined && msg != "") {
$("#" + ctrl).html(msg);
$("#" + ctrl).show();
}
else {
$("#" + ctrl).hide();
}
</script>
NOTE:the script simply checks to see if the hfMsg control has a message to display or not.
and add the following two methods to the master page:
public void ShowMessage(string control, string message)
{
this.hfCtrl.Value = control;
this.hfMsg.Value = message;
}
public void ClearMessage()
{
this.hfMsg.Value = string.Empty;
}
finally you can call the ShowMessage method from any page like this to display a message on the master page:
Master.ShowMessage("lblMsg","hello world!");
and if you have a user control that holds an html label (e.g lblUserMsg) to display the message you can simply call ShowMessage and pass it the name of the label:
Master.ShowMessage("lblUserMsg","hello world!");
Having a SetStatus method in the MasterPage is always the way I've done this, to access the MasterPage from inside a user control, just create a private property in the usercontrol (or create a baseControl class that all user controls inherit from):
private TheNameSpaceOfMyMasterPage.MyMasterPage Master
{
get { return (TheNameSpaceOfMyMasterPage.MyMasterPage)Page.Master; }
}
protected void btnSave_OnClick(object sender, EventArgs e)
{
// Do your stuff...
// Set the Status
this.Master.ShowStatus("blah blah blah");
}
Also if you're using a control to hold the status message remember to disable ViewState on it, otherwise you'll end up with the same status message across postbacks which you don't want.
Some good answers, but...
To Robert W: the master page impl works, but it does require strong coupling (knowledge of) with the master page type. Master pages should generally affect style only, right? E.g. I should be able to change master pages without breaking my app.
SubPortal: yes, very clever, but... too clever for me. Also has master page issue.
RPM1984: again, too clever for me!
MGOwen didn't mention any special DHTML requirements (e.g. update from client side). So why not just implement a simple server-side helper method as he mentioned, find the target control which displays the message, and display it?
The following ShowMessage will find the target message control wherever it is on the page, as well as enable any page to override the default application's ShowMessage behavior if desired.
public static class ASPHelper {
// Defines something that shows a message
public interface IShowMessage
{
void ShowMessage(string msg);
}
// default implementation: finds a target message display control
// wherever it is on the page.
static void ShowMessage_Default(string msg)
{
const string SHOWMESSAGE_CONTROL_ID = "ctlShowMessage"; // or whatever
// find the control
Page currentPage = HttpContext.Current.CurrentHandler as Page;
Control ctlMessage = currentPage.FindControlRecursive(SHOWMESSAGE_CONTROL_ID);
if (ctlMessage == null)
throw new Exception("ShowMessage control not found!" );
Literal ctlMessageLiteral = ctlMessage as Literal;
if (ctlMessageLiteral == null)
throw new Exception("ShowMessage control must be a Literal!");
// Message control should not implement viewstate -- unneccesary
Debug.Assert(ctlMessageLiteral.EnableViewState == false);
// show it
ctlMessageLiteral.Text = msg;
ctlMessageLiteral.Visible = true;
}
// public version for use across app & in pages
static public void ShowMessage(string msg)
{
// Allow the current page to implement its own way of showing
// messages -- provides flexibility.
Page currentPage = HttpContext.Current.CurrentHandler as Page;
IShowMessage showMessageImpl = currentPage as IShowMessage;
if (showMessageImpl != null)
{
// Show using custom message displayer
showMessageImpl.ShowMessage(msg);
}
else
{
// static/global/default version
ShowMessage_Default(msg);
}
}
} // end ASPHelper
To use, simply place a literal control on the page, as in:
<div><asp:Literal
ID="ctlShowMessage" runat="server"
Visible="false"
EnableViewState="false"
/>
</div>
To use, simply call ShowMessage, as in ASPHelper.ShowMessage("insufficient credit"). Hope this is what you're looking for... Keith
Javascript safe popup. Works with Ajax/jQuery.
Namespace Utilities
''' <summary>
''' Utility class for injecting JavaScript into pages. Used primarily for throwing a JavaScript alert box, with correct focus.
''' </summary>
''' <remarks></remarks>
Public Class WriteJava
Region "Public Subs"
Public Shared Sub Script(ByVal script As String, ByRef p As Page, Optional ByVal scriptName As String = "")
If String.IsNullOrEmpty(scriptName) Then
scriptName = GetScriptName(p)
End If
If Not p.ClientScript.IsStartupScriptRegistered(scriptName) Then
ToolkitScriptManager.RegisterStartupScript(p, p.GetType, scriptName, script, True)
End If
End Sub
Public Overloads Shared Sub Alert(ByVal MyAlert As String, ByRef p As Page)
Script("alert('" & Format(MyAlert) & "');", p)
End Sub
Private Shared Function Format(ByVal value As String) As String
Return value.Replace("'", "\'").Replace(Chr(13), "\r").Replace(Chr(10), "\n")
End Function
Private Shared Function GetScriptName(ByVal p As Page) As String
Dim i As Integer = p.AppRelativeVirtualPath.LastIndexOf("/")
Dim pageName As String = p.AppRelativeVirtualPath.Substring(i + 1)
Return pageName
End Function
End Region
End Class
End Namespace
Use by calling:
Utilities.WriteJava.Alert("DANGER WILL ROBINSON", Me.Page)
I was looking for a site-wide way to display message to the user. I found jnotifica. It's similar to stackoverflow's bar at the top of the page.
The author's site appears to be down at the moment.
Raise an event in the user control, subscribe to the event from the page. The event handler updates your custom page property. Seems like the least amount of moving parts.
I would like to suggest to use a class for custom page(Inherited from System.Web.UI.Page) inside that add follwing as
protected void AlertError(string ErrorString)
{
StringBuilder scriptBuidler =
new StringBuilder(#"<script type='text/javascript' language='javascript'>");
scriptBuidler.Append(#"alert('");
scriptBuidler.Append(ErrorString);
scriptBuidler.Append(#"');");
scriptBuidler.Append(#"</script>");
AjaxControlToolkit.ToolkitScriptManager.RegisterClientScriptBlock
(this, typeof(Page),
"Patient Detail Not Found",
scriptBuidler.ToString(),
false
);
}
and inherit all your pages from this class instead of inherinting from system.web.ui.page
and use this function to to show your messages to your clients

How can I copy the DynamicData templates from another site?

I'm attempting to start using DynamicData functionality in a previously existing website. Basically I'm following this tutorial. When I got to the part about creating the Field Templates I decided I could probably create a new site with the Dynamic Data stuff built in, and then just copy the folder over.
Unfortunately when I do that and try to compile I get the error "Could not load type..." for just about every .ascx file in the DynamicData directory. I named the "new" project the same as the pre-existing site so that the namespace would be the same... but I can't think of what else I could be missing.
Everything looks ok, except that the *.ascx.Designer.cs files are showing inside the Solution Explorer. I tried deleting one and then copying that file back into just the directory but it didn't work. I'm assuming I need to do something special with those so that Visual studio handles them properly and can compile?
Here is one of the .aspx files:
<%# Control Language="C#" CodeBehind="FilterUserControl.ascx.cs" Inherits="EService.FilterUserControl" %>
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="true"
EnableViewState="true" ontextchanged="new">
<asp:ListItem Text="All" Value="" />
</asp:DropDownList>
Here is the matching .cs file:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Collections.Specialized;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml.Linq;
using System.Web.DynamicData;
namespace EService
{
public partial class FilterUserControl : System.Web.DynamicData.FilterUserControlBase
{
public event EventHandler SelectedIndexChanged
{
add
{
DropDownList1.SelectedIndexChanged += value;
}
remove
{
DropDownList1.SelectedIndexChanged -= value;
}
}
public override string SelectedValue
{
get
{
return DropDownList1.SelectedValue;
}
}
protected void Page_Init(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
PopulateListControl(DropDownList1);
// Set the initial value if there is one
if (!String.IsNullOrEmpty(InitialValue))
DropDownList1.SelectedValue = InitialValue;
}
}
}
}
And here is the .ascx.designer.cs file:
//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated by a tool.
// Runtime Version:2.0.50727.1433
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
namespace EService
{
public partial class FilterUserControl
{
protected System.Web.UI.WebControls.DropDownList DropDownList1;
}
}
EDIT: If I create the file in the website, then copy the contents from the temporary site I created it seems to compile just fine. Really have no idea what the issue is here... I tried manually modifying files to match the results of copying and they still wouldn't work unless I actually created them in the site. It's just bizarre...
The problem was due to the temporary site creating the <%# Control > definitions with the CodeBehind property instead of the CodeFile property. For some reason pages in the actual website will only compile when CodeFile is declared...
DD will work with Either Website or Web Application. however when copying in from an other project the types need to be the same otherwise it's lot of editing to convert swee my article here Getting Dynamic Data Futures filters working in a File Based Website.

asp.net output data from DB without any html markup

I'm new to jquery and asp.net so please forgive if this is an obvious question. I'm using a jquery autocomplete plugin which requires that the page it looks up asynchronously for data is in this format as pure text only:
product1|price1
product2|price2
product3|price3
WITHOUT ANY OTHER HTML MARKUP. Any other html tags seems to cause problems.
Normally for a page like that I would use a repeater and some standard database calls and output the 2 fields. This however creates html tags.
How can I output this data as text only with no other markup whatsoever?
If you have a bare page with no master page referenced a repeater shouldn't produce any html. Make sure in the HTML view you only have:
<asp:Repeater ID="outRepeater" runat="server">
- your template here
</asp:Repeater>
An alternative would be to add a new Handler to your project which is a class that implements the IHttpHandler interface. This would allow you to output your code directly. This would end up looking like:
public class MyOutputHandler : IHttpHandler {
public bool IsReusable { return false; }
public void ProcessRequest(HttpContext context) {
context.Response.Write("product1|price1");
}
}
If you have added this to a project as a new Handler (from add items) it should have a .ashx extension. Otherwise you'll need to register it in your web.config with its type and filename.

Resources