Web Forms :: Changing The Value Of An "Input" Field Dynamically From Code Behind File
Jan 16, 2011
I have this in my code-behind file (VB.NET):
[Code]....
Here is the HTML source of the part of the page:
[Code]....
Where that comment in the code-behind file says "REFERENCE IN CODE HERE", that is where I want to set the value of the "remLen3" input (client-side control) to "30 characters left."I obviously left out irrelevant things like inserting the txtNewComment.Text into the database. But what's going on here is when the user types in something into the txtNewComment text box, I'm using javascript to change the value of the remLen3 control.My problem is that when I submit the text from the txtNewComment textbox to the database and set the txtNewComment.Text equal to Nothing, I don't know how to reset the remLen3 field value back to saying "30 characters left.". I already tried to add a "runat="server"tag to it, but when typing stuff into my txtNewComment textbox it gives me an error. I already tried to figure out what the error meant, so I'm not going to spend time trying to solve it anymore; I would rather just see if there is a workaround to using the runat="server" tag. Maybe do some kind of a CType(FETCH_REM_LEM3_HERE_SOMEHOW, INPUT_TEXT_TYPE??).value = "30 characters left". If there is a way of converting the input text control (remLen3) that way, then how would that be done? I just want to change the value of that field when the server-side button is pushed.
I want to integrate paypal inside my shopping cart. For that it requires a html form to be embeded inside .aspx page with the action to paypal and method is post. Inside that form there are some hidden input filed. I want to assign one of those hidden field's value from server side code so i need to access that filed from server side. But how? Here is my form:
I have a code behind file which has only a few placeholders and literal. The gridview control and others are added in real time according to program conditions. I noticed that once in a while th eprogram stopped working because the .aspx file is changed and some of the place holders disappeared - Why? (the bolded lines disappeared once in a while)
What I need to do is perform some kind of decision statement and when true I need to change the backcolor of a treenode to grey, so that it has a grey box around the whole text. There is no backcolor property for the tree node and I don't need it applied all the time so I don't think a CSS class will do this.
Scenario: I have a form with 3 input fields (text1, text2, text3). Is there a method to capture these fields in the aspx file of a second webform? I think you have to use someting like <%= %> but I'm not sure.Idon't want to use the code behind file because the number of input fields is dynamic
I have a DetailsView on the page and I have made one of the fields a TemplateField. In the EditItemTemplate and InsertItemTemplate I have a DropdownList that is databound to a table in my Sql Server database. I wanted to add an initial value to the DropdownList namely "- select -" .
I set the AppendDataBoundItems property to true and added the initial value as a ListItem.Markup of the DropdownList
This works fine for new input. The problem is however that the database already has records that were entered through a Windows Application and many of these records has a null value in this field and exceptions are thrown when I tried to open these records and the system tried to set the SelectedValue of the DropdownList.After some more searching I found this help
This now solved the problem of opening a record where the value is null in the database, BUT now the RequiredFieldValidator is not validating anymore to make sure that a databound item is selected for this field and not the initial value "- select -". So basically now it is not checking anymore to see if valid input has been entered for the DropDownList and it accepts "- select -" thus it acts as if the field is not a required field anymore.
In short what is required is that I want to make sure that the user enters a valid selection in the DropDownList, but it must also cater for old records that do not have this field entered yet so that those old records can be opened in the DetailsView .Opening Old records (with null in that field):When these old records are opened in the DetailsView the DropDownlist should show "- select -" when the value in the database is null.
Saving records (old or new records):When saving the record in Insert mode or Update mode the RequiredFieldValidator should show that a valid input is not selected if the DropDownList is still on "- select -".
I've tried to override error message when input incorrect data type in input field on HTML form.For example I have the model like this.
public class Person { public string FirstName {get;set;} public int Age {get;set;} }
For view, I put text input for Age to get it value.When type some string in Age text box like 'test' and press submit button. I got this error message ,The value 'xxx' is not valid for AgeHowever, I want to change this message and try many way. There 's nothing effect this message value.
In my asp.net application i'm using gridview to which i'm binding data dynamically by writing a select query in code behined file (all column's are autogenerated) now i want to change gridview cell to edit mode from label to textbox or dropdown on clicking of gridview's cell.How can i achive this in code behined file.
I have an ASP.net page with two textboxes where the user types in input. I applied a requiredfieldvalidator to both textboxes as well. However, I also want the textboxes to change to a backcolor of red if the form is invalid when the user clicks the button to submit the input. I tried this code below in tthe button click event, but doesnt work...
If Page.IsValid = False Then txtCosts.BackColor = Drawing.Color.Red txtRevenue.BackColor = Drawing.Color.Red End If
How else can I change the Backcolor of the textboxes when the input is invalid.......
i have an microsoft .office.interop.excel(dll) located at an directory d:abc. now i do not want to add them as an web reference in my projet and call them
rather call the dll dynamically from my code behind(.cs) is ther any way we can do dynmically
I'm trying to dynamically load an image from my code behind file, however I want to be able to resize the image thus reducing the file size sent to the client. I've come across a few samples but without much luck. So far I have the following:
[Code]....
Unfortunately I now need to load this image into control panel...but nowhere can I find how to do this.
I have static html paypal buynow button that works great, but it's static.
[Code]....
But it is possible to change the values for the hidden inputs from .net codebehind code? I found this post which takes a different approach of sending these hidden fields instead as a query string to paypal. Not sure I like that though as would this not possiby explose some of those fields like the return page?
Basically what id like to do change the important parts of the button and info I'm sending to make it dynamic.I know I can do something like this in the markup, but that would mean having to fetch data mulitple times was hoping I could somehow adderss the field values directly in the codebehind. Or possibly dynaically generate and insert the entire changing input type fields from the codebehind
Possible to add them with something like this: myform.Attirbutes.Add (???). If so how do I contruct these input types in .net?As far as return logic security, I've tested that it's solid, i just need to automate the button process so I don't have to create a buy now page and button for each product.
This may be a simple question but here it goes. I have an insert form that captures the current date of entry. What I would like to do is not cause the user to enter or select the current date but have it display on page load and capture to the field in the table on submit.I am rather new to ASP and am using Visual Web Studio 2008.
very first when the page loads the focus willl be on the next button, when i try to enter the text in the text box, focus changes from the next to the previous button (Previous button is the first button i have).
When I change my insert update and delete buttons to template field....they do not work properly anymore. I get a "Cannot insert a Null Value into...blah blah blah, error.
We have a database with around 5000 records in it. We also have a web page that displays many of the fields. One field is an nText field and displays up to several paragraphs. My customer wants me to add those A+ and A- buttons for increasing and decreasing the font size for this field. My problem is that many of the older records have quite a bit of formatting in the field. Most of the rest contain styles dictating a font size of 12 px. Is there a way to increase and decrease the font soze of the text without modifying all the records?
I'm working on a project that have 3 diffrent type of users with 3 diffrent master pages. I can verfiy there access level and let them view pages but after googling I came accross a tutorial form asp.net but it wasn't very helpfull the code I got listed below works only if the session is at null, It dosen't seem to pull the session value.
[Code]....
there is a class page attached to it but nothing seems to work. I've downloaded the tutorial but it wasn't any clearer than what I read.
I 'm just trying not to have to code over the joint pages.
I have a grid view that I want to dynamically change based on data in my page. Specifically I want to change one of the title items and I want to hide a column based on a certain condition.
I have an html input control that is a radio button. This radio button needs to disable required field validators when selected. This is my non working code so far. What have I not done?
I'm writing a script and need with being able to modify the ImageUrl property in a HyperLink control from the code behind page. It is meant to dynamically show an image.
I just need to know the correct format of the code behind to get this to work.
I've got a details view control on a page. One of the columns, from the database table, is a bit field. It is not nullable, and that's the way it has to be. Also, in most cases, when inserting data, it will be true (1) be default. I've found in testing, when inserting data, that it was false, for some reason. So, I changed the column to a template field and went to the InsertItemTemplate for that column, and changed the checkbox Checked property to True, instead of the default False. However, it has really screwed up the page because now it won't save anything at all! When I try saving something using the details view, it does show the checkbox as being checked, but man, once I try saving it I get an error message back from the database saying that the column doesn't allow for nulls.
Huh??? How in heck can the column on the page have a value (it is checked), but when it goes to save something it fails? Furthermore, before I converted this field to a template field, it worked perfectly. I tested several other insertions, and they all worked. But when I converted it to a template field, it stopped working? What's that about? I even tried setting the default value for the Checked property of the checkbox back to False, but that still doesn't work, it still wants to pass in a null. What's going on here? Why is it that converting a field to a template field, which was working perfectly fine before I made the convension, stop it from working at all?
