AJAX :: File Upload Control Does Not Maintain Their State After Post Back?
Jan 24, 2011
I am using file upload control and the captcha.After fulfill the form and upload the file , if user enter the wrong captcha test and click on button the uploded file being disaaper .I know this is the shortcoming of file upload control but client required thatIt needs to not clear the photo Plz help me out so that i can maintain the uploaded file state and have to capable so that user does not need to uploaded file again.
My <input id="FileUpload1" name="FileUpload1" type="file"> and country dropdown both are inside update panel , now on selectedindexchanged it do postback , which i am triggering in update panel to avoid page refresh .
Now the problem is when i select any image in fileupload and then select country , my selectedimage vanishes but its path stays in textbox .
I'm using a asp file upload control, however, when other controls trigger some post back actions, the file upload value return to null...any sample code i can follow please?
i find out that whenever there is a post back, the page will post back and go up to the to the top position of the screen. Is it posible for it to maintain the location as it is as before postback??
I have a parent control that has an instance of a HiddenField child control. I am using CreateChildControls() to add it. Everything works client side including the values being added to the field. However, on postback, the reference to the field is null
here is the code
[code]....
I have tried simply relying on the ViewState ... then also attempted using FindControl(). Neither works, it comes up as a null reference ... any input on what is going here?
I have four controls in a page with update panel.Initially mouse focus is set to first control.when I partially post back the page to server the focus automatically moves to first control from the last focused control from the control I have tabbed down to.Is there any way to maintain the last focus?
I am using usercontrol to populate a web part. The user control consists of ajax tab and in it there is another user control which is a gridview. I add the tabs - My top level usercontrol to the web part. Now when user makes a selection in the gridview (this does a postback) I would like to maintain the scroll position. I tried adding - this.Page.MaintainScrollPositon = true to the page load event of my tabs (priamary) user control. But it does not seem to work. Is there any other way to maintain position in a web part.
I am using the async file upload control to upload to a image file. I want the user to upload only jpg files. And for that I am checking the uploadedfile content type in server side, after the upload complets. I wanna check this, before upload starts. There is one javascript method
function startUpload(sender, args){}
but how to access the content type of the file selected by user.
I was just wondering if its possible to do an ajax post a file in asp.net mvc,basically i have a form with two buttons, one of the buttons extracts images for the selected document and displays them for the user to choose thumbnails for the document he is about to upload. The usee then fills out the rest of the form and then saves the document.With the image extraction, I was owndering if it was possible to do that as an ajax post. The other submit button can work as a normal http post
I've seen a good few questions like this around but havnt actually come across any articles with the answer (maybe just been unlucky with my research!).
Basically I'm looking to have say 3 links (or buttons) on a page, which in turn will dynamically load a specific user control into an update panel with AJAX.
Then I would like the usercontrol loaded to be capable of handling postback within the update panel (basically no page refreshes) to do its processing and return output.
Does anyone have any pointers to articles/blogs covering this?
I've seen many but non covered handling postbacks from the user control or handling the postbacks within the update panel.
I have a system that has several large objects that need to be built and populated each and every time, and these objects may be accessed quite often as well. As a strategy, caching would not be that good for me because there are potentially thousands of these objects which are fairly large. So I propose to serialize the objects to the file system and then deserialize it when I need those objects again. I have several classes that need this serialization functionality.
These objects change as well, so on the next access I check if there were any changes and then I grab only the changes and edit the object, and then reserialize the object.
My question is what is the best way to do this, since I have several classes ..
I searched google and found asynchronise post back trigger is used if we want update panel to post back on some event of control if it is out side the update panel. Than what is purpose of post back trigger ?
I have a requirement where i need to add file upload contorls dynamically.Intially i have a upload control in my page and button named 'Add fileupload' and another button named 'Upload'.the fileupload control is added dynamically when 'Add fileupload' button is clicked andUpload button is used to upload the files.when i click on 'Add fileupload' button after browsing the file to fileupload control, the new fileuplaod contorl has been adding successfully but the first fileupload control is empty.Can any one please help me how the state of fileuplaod control is maintained.Here is the code
could any body explain me how can i save state of two list boxes on post back i am using jQuery of this kind i dont know on what event what should i do or where can i save view state or how can i use hiddenField to persist the state of both list box
I have an asp.net panel having various controls including gridview. I have converted this panel into pdf and attached it as an email attachment using memory stream. Everything is working fine. Now I have an File upload control outside panel through which I have to attach a file and send it in mail along with the already attached panel. But I am unable to figure out how to do it.
I have four textbox and a button in my page. After filling the textbox. When the user click save button. A loading image should be displayed. User should not feel that the page is postback to the server,Some thing like in facebook loading image.
Being new to ASP.NET I have run into trouble building my own Whack-a-mole program. I think my problem comes from using Buttons, which by themselves send post backs to the server, making the software unusable. The looks are in place, making new buttons show up in the grid, in different places by random. However, when a button is pushed - the score doesn't change (which I feel is strange).
Not so strange is that the Button doesn't work since it sends post back to the server - reloading the UpdatePanel. I think I should use a different controller like the CheckBox and style it hard using CSS (which isn't a problem). Is this the correct way to go, or should I make use of JavaScript AJAX instead?
Note to self: This technique shouldn't be used in a public application since it put too much unwanted pressure on the web server.
I have created a matser page with a two radio buttons, text box and a button. Whenever user sets some values to these control and clicks the button, i will navigating him from one content page to another based on the data he has entered. The problem is after the content page load, the values selected/given in the controls(radio button, text box) are getting cleared.
I am trying to make a custom server control which inherits from DropDownList. I give the control an XML input containing some key/value pairs and my control shows them as a DropDownList.I make the list items in the override Render method like this:
we developed two forms.asp x with Dynamic Controls,First form has one Dynamic button_Open ,this button has Click event ,through button_Open_Click event we need to open second form with dynamic controls through (window.open()),window opening but forms.asp x not displaying controls and Second form overwriting on first form ,we added code for Dynamic Controls in both pages Page_PreInit event.do the better way to maintain state of control both pages?
i am new to this ASP.NET and AJAX.I am trying to learn AJAX. I Have one doubt.what is the difference between normal file upload control and ajax AsyncFileUpload Control ..?
