Can i read data from web.config using JQuery ?
Jquery is javascript that runs in your browser, your web.config resides on your server. If you want to expose data from your web.config, I think you should create some kind of webservice that you can call from the client side javascript to get the data you want.
If you would be able to directly read from the web.config file, then it would be a major security risk as the web.config file is often used for storing sensitive information like connection strings etc.
The best solution when using none aspx/HTML5 :
1.Create file "Web.config.js" (java script file) in the project root
2.Add ref to the JS in your HTML file
<script src="Web.config.js" type="text/javascript"></script>
3.add the key & val to the "Web.config.js":
var prmKEY = "myVal"
4.Access prmKEY from JQuery as global parameter
You can also store the data as a cookie in the OnPreRender(EventArgs e) or Page_Load(object sender, EventArgs e) (if your using the Page_Load() store the cookie in the if (!IsPostBack){} so your not storing it multiple times) and read it on the client side to use for whatever purpose. I usually store data such as this as session storage on the client side to use while the program is running.
Server side:
// **This works best if the property isn't a data structure, otherwise you will need to do**
// some data manipulation to get it to work right
Response.Cookies["FOO"].Value = MyApp.Properties.Settings.Default.FOO.ToString();
Client side:
sessionStorage.FOO = readCookie("FOO");
No, you cannot.
I found solution without making any web service :
1- building empty aspx page that in it's load read the data from web.config and write it in the page using Response.Write(**)
2- using JQuery to read the result from created page as follow :
$.get
(
"JQueryPage.aspx",
function(result) {
// .. set variable to result and use it
}
};
In Page Load event store the config value in hidden fields using Config Manager.
Retire from hidden fields using J query.
You can create a hidden textbox with variable on html and assign value from config file to it. Assign a id to the hidden control and grab details of that using jquery.
I'd assume you could read the value from your webconfig in your controller. Inject that value into your view and then use jQuery to retrieve that value. That would be the way I'd approach it. I'd place it in my appsettings element. Shown here how to get from your webconfig. https://msdn.microsoft.com/en-us/library/610xe886.aspx , then I would inject that into my view using Viewbag.
Related
I want know which page and which URL has calling my Handler .ashx, is that possible?
I need this because, I have an Handler who calls and convert images from database, but some of my URLS of images are not passing the right query argument (they don't exist in database) and I need what is the URL who call to see what is the image for that arguments.
why not just use
context.Request.UrlReferrer?
A quick solution to your immediate question is to call (in C#)
Inside your public void ProcessRequest(HttpContext context){} method, add the following 3 lines.
IServiceProvider provider = (IServiceProvider)context;
HttpWorkerRequest worker = (HttpWorkerRequest)provider.GetService(typeof(HttpWorkerRequest));
String referer = worker.GetKnownRequestHeader(HttpWorkerRequest.HeaderReferer);
This will give you the URL of the page that called your handler.
To go further though, you should ideally be implementing error handling to handle any missing images.
What I'm trying to do here is to allow my user to select a path in a data server on a network, so that I could generate a configuration file.
I hope to be able to replicate the function of OpenFileDialog() on my asp.net page. However this function does not exist on asp.net, and I do know that there is this control in asp.net call FileUpload. But what I required here, is just the path/directory for the folder. I do not require my files to be uploaded.
How can it be done?
Doing this in a web application is tricky. You would have to enumerate the folders on the server that you want to browse (presumably this is the same server that's running the web application), and then present that hierarchy to the user to select a folder. If it's not too big a hierarchy, you could just enumerate the whole bunch up front, and display it in a tree. If it's big for that, you could use an Ajax approach: select the top-level folder, then send an Ajax request to get the next level, and so on.
To enumerate the folders, you'll need to walk the filesystem yourself. See http://msdn.microsoft.com/en-us/library/dd997370(v=vs.100).aspx for one way.
No, there is no inbuilt control for this. It is not a normal requirement cause most site don't let their users see their file structures.
Building a user control that does this will be simple though.
I suggest using a TreeView asp.net control, attached to your datasource where you have listed the files.
This sample on binding a treeview should get you started.
You can populate your data using
var path = Server.MapPath("/");
var dirs = Directory.[EnumerateDirectories][2](path);
var files = Directory.[EnumerateFiles][3](path );
Finally to make it look like a dialog, you could use the jQuery UI dialog component.
The solution I have found is, this is just for anyone looking for answer:-
protected void browse_Click(object sender, EventArgs e)
{
Thread thdSyncRead = new Thread(new ThreadStart(openfolder));
thdSyncRead.SetApartmentState(ApartmentState.STA);
thdSyncRead.Start();
}
public void openfolder()
{
FolderBrowserDialog fbd = new FolderBrowserDialog();
DialogResult result = fbd.ShowDialog();
string selectedfolder = fbd.SelectedPath;
string[] files = Directory.GetFiles(fbd.SelectedPath);
System.Windows.Forms.MessageBox.Show("Files found: " + files.Length.ToString(), "Message");
}
The asp.net site is a completely disconnected environment to your server. As other people have mentioned, to replicate an OpenFileDialog() you will need to look at the folder structure and present this to the user in the web/disconnected environment. In this case the user is abstracted from the actual file system... since this abstraction already occurs, it would be a good time to consider the route you're taking. It might be worth considering that a direct replication of the file system is not required, you could manage the "virtual" folder structure in the database with links/paths to files on disk are maintained there?
I have a global.asax in which I define some variables that I want to be available throughout the application, such as a class to handle certain database requests. In an aspx page, I can access these variables/objects using for example in Visual Basic:
dim dataMan as clsData = application.get("dataGofer")
My question: is it possible to call this from a generic handler (.ashx file)? If so, can you please show me a code snippet? Thanks!
You have Context parameter of ProcessRequest method through which you can access the page objects.
Dim value=context.Application.Get("key")
I am re-writing an ASP.NET application and noticed a difference in behaviour ...
In my Page_Load event I have some code such as:
string id = Request["id"]
which gets the id param from the URL. On page load (ie a HTTP GET), this works as expected in both versions. I also have a button onclick event handler. Clearly, this performs a POST to the server, and also invokes the Page_Load handler. The difference is, that in the original version of the app, the id is successfully loaded from the request. In the new version of the app, id comes back as null. I have discovered that I need to use Request.Params["id"] instead, but am totally puzzled as to why Request["id"] works for POST requests in one app but not the other.
The only difference between the apps is that the first was created as File -> New Website and the second File -> New Web Application. I think this is what is causing the difference in behaviour, but am wondering why this subtle difference, and also if there is anything else I should be aware of between the 2.
Any advice greatly appreciated.
As you have mentioned, you have the id parameter coming through twice. This will be because you have one in the query string parameters and one in the form parameters. I'm not sure why this would be occurring in one web app and not the other, but you can make changes to your code to account for it in a more correct way.
If you view the source of the HTML in your browser, you will see that the action value for the form will be current pages URL, including the query string. This is why the first id is being sent through. Evidently, the second id is coming through via the form itself:
HTML Source of basic web form
<form method="post" action="Default.aspx?id=3" id="ctl01">
<input type="text" name="id">
</div>
There are a couple of things you can do here:
first off, I wouldn't use Request.Params["id"] for this, as it combines the query string, form, cookies and server variables into one collection. You should use Request.Querystring and Request.Form properties, based on what you require and when
In your Page_Load handler, use the Page.IsPostBack property to determine whether the page is loading for a GET or POST and use the Request properties described above.
Example of Page.IsPostBack usage:
protected void Page_Load(object sender, EventArgs e)
{
string id = string.Empty;
if (Page.IsPostBack)
{
id = Request.Form["id"];
}
else
{
id = Request.QueryString["id"];
}
}
I always use web applications project but the difference is compilation. Website has a dynamic compilation, which means that the first request will be slower and web app has pre-compiled release dlls.
Check this for pro's and con's : http://maordavid.blogspot.ca/2007/06/aspnet-20-web-site-vs-web-application.html
I created an asp.net Server control that derives from a LinkButton, and renders a small javascript function to the page.
I want to use this control many times on the page, but just want the javascript to be rendered once on the page. On the other hand, I rather not manually add it in a js file, because i don't want to have a chance of forgetting to add the js file in the future.
What will be the best way to go about doing this ?
Preventing duplication in client scripts
Use a registration method such as Page.ClientScript.RegisterClientScriptBlock(..). There are a couple of overloads but they all work in a similar fashion. It's smart enough to render the script only once no matter from how many control instances it's issued.
Microsoft remarks in the MSDN documentation:
A client script is uniquely identified
by its key and its type. Scripts with
the same key and type are considered
duplicates. Only one script with a
given type and key pair can be
registered with the page. Attempting
to register a script that is already
registered does not create a duplicate
of the script.
The MSDN docs also contain sample code such as this:
// Check to see if the client script is already registered.
if (!cs.IsClientScriptBlockRegistered(cstype, csname2))
{
StringBuilder cstext2 = new StringBuilder();
cstext2.Append("<script type=text/javascript> function DoClick() {");
cstext2.Append("Form1.Message.value='Text from client script.'} </");
cstext2.Append("script>");
cs.RegisterClientScriptBlock(cstype, csname2, cstext2.ToString(), false);
}
Other similar registration methods
Different methods can be used to register your client script in different ways - see each of the ClientScriptManager.RegisterClientScript*(..) methods in MSDN for more detail about each. They're all built to prevent duplication in the rendered page.
This gives you the freedom to output scripts at the control level without worrying or having to track or count scripts.
Edit:
The ClientScriptManager instance is accessed through the Page.ClientScript property.
You can use the Page.RegisterClientScriptBlock method.
Here is an example from the MSDN:
if (!this.IsClientScriptBlockRegistered("clientScript"))
{
// Form the script that is to be registered at client side.
String scriptString = "<script language=\"JavaScript\"> function DoClick() {";
scriptString += "myForm.show.value='Welcome to Microsoft .NET'}<";
scriptString += "/";
scriptString += "script>";
this.RegisterClientScriptBlock("clientScript", scriptString);
}
HTH
Any way to reference a script on a CDN and not have it duplicated multiple times? Or can I just not worry about it since it's just a pointer anyway and the browser is (?) smart enough not to load the same library twice?
In other words, suppose I want the following code inserted from a server control:
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
If I use a RegisterClientScriptBlock I can use the IsClientScriptBlockRegistered method to not have the server control load it multiple times. But, the preceding code is likely to have been put on the page anyway by either another (different) server control or by the developer who wants to use jQuery for something outside of the server control.
How do I get the server control to not load the script if the developer already loaded it?