I'm very new to Visual Studio and I am getting this error when trying to update an Oracle table from Gridview using a tableadapter datasource. I've followed the instructions in my text very closely but am at a loss as to why this error is occurring.
Details: System.MissingMethodException: No parameterless constructor defined for this object.
Source Error:
[Code]....
Stack Trace:
[Code]....
this is the stack trace error I am getting. At this point, I'm a little clueless how to resolve it.
I receive the error "No parameterless constructor defined for this object", I have read some post on this forum about this error, but i cannot get it to work.
First I incorrectly had my node defined in /shared/web.config instead of the web.config in the root of the WebUI project. I also had not correctly defined my connection string within web.config. I have pasted the proper web.config sections below:
I've set up a strongly-typed View and a controller method to save the object represented in that View. The object in question is from a class that uses named parameters with default values. This is not a database object, but rather is the intermediate object that is used for the display and user input. It gets translated into a database object in the service class. Anyway, when I attempt to save the object, I get the following error:
System.MissingMethodException: No parameterless constructor defined for this object.
This is kind of aggravating. I can add a parameterless constructor to the class, and then everything works just fine. I just don't understand why it is necessary. I'm new to named parameters with default values, but the reading and such that I've done has described that method calls with default values do not have to have a 'no-parameter' implementation. You can just call the method with any or none of the parameters specified and everything works as expected. If there is a 'no-parameter' implementation and no params are passed, then that one is used, since it is more specific than the one with default values. Is the behavior somehow different when this is used in the constructor of a class? Why would I have to include a parameterless constructor when I have all the values accounted for? Is the runtime creating an object on the fly as the save method executes, which requires this? The method is like this:
[Code]....
I'm wondering if the object is instantiated by the runtime in order to populate the method parameter, and then assigned values from the form collection. I suppose that would make sense, but I do not understand why this causes an exception. For what reason would a parameterless constructor be required?
I have no idea why my form submit is not passing the model back to the Controller action
Here is the View:
[Code]....
Heres the Controller:
[Code]....
Here is my Model:
[Code]....
By default Index, renders with an empty results set, on button press i want it to go to the "StartSearch" Action, and rerender the index with possibly non-null results set.
Does anyone have any good examples of how to make Unity 1.2 or 2.0 work with ASP.NET WebForms?
I thought I had this figured out, but evidently I'm missing something. Now I'm getting the error; "No parameterless constructor defined for this object". I remember getting this error a couple years ago, I and just don't remember what I did.
Obviously Unity isn't working as it should because somewhere along the way I've forgotten something.
I have impelemented my own mvc pattern to my website , when I add desired type for my ObjectDataSource pointing to the controller class although GridView refreshes schema in designer just fine I get an error in runtime saying : "No parameterless constructor defined for this object." which is self explaining but I wonder why does it happening because I've used this pattern once and didn't have that issue , here is the bit of code that is causing this issue , what to do to keep my mvc and make it work :
I have a usercontrol which implements iwebpart and this is loaded into a webpart by adding it to the webpartmanager on the page. But i'm getting the error message "No parameterless constructor defined for this object." and i cannot find out what i'm doing wrong. The control is loaded into the webpart by:
I've created a web service , which can a method to set the user credential using Microsoft.Web.Services3.WebServicesClientProtocol. The sample code is :
<WebMethod()> _ Public Sub ClientCredential1(Of TSecurityToken As SecurityToken)_ (ByVal UserCred As Microsoft.Web.Services3.Security.Tokens.UsernameToken)
[code]....
When I run the web service it gives this error: "Microsoft.Web.Services3.Security.Tokens.UsernameToken cannot be serialized because it does not have a parameterless constructor."
i am taking data from two tables so i created one class and i constructed with two tables like this..
[Code]....
my edit post method is:
[Code]....
if i put PublisherViewModel in post function edit (ByVal aintEntityId As Integer, ByVal model As PublisherViewModel) As ActionResult. i am getting this error when post edit function called. No parameterless constructor defined for this object.
This was a pretty disappointing moment - when databinding, using Eval("Contact.LastName") would work. It nicely evaluates the related Linq object's member LastName. If the "Contact" object is null, no error is thrown... instead the field is simply null.
However, the same does not hold for sorting - if there exists a null entry (this object does not have a Contact) then the LinqDataSource throws a NullReferenceException. This means that, if you ever have nulls on your foreign-key objects, you can't use sorting headers in the ListView.
This makes the feature moderately useless - I have to roll my own properties for every single field I'd ever want to sort on. That's insane.
My Problam is on Capturing Text Box and Dropdown seleted itam from grid view i create a gridview with Empty DB binding using [URL] this senirio. I only used setinitional value() function and called its in page load as discribed in above lonk. insted of adding New record Button i callled a java scrit code discribed below. and i also create a button (SAVE) to capture a value intered in text box . On this button click event i try to capture a textbox and dropdown value like
for (int i = 0; i < Gridview1.Rows.Count; i++) { DropDownList sen_to1 = (DropDownList)Gridview1.Rows[i].Cells[1].FindControl("DD_sento_org"); TextBox Add_to1 = (TextBox)Gridview1.Rows[i].Cells[2].FindControl("Txt_addto"); int Add_to = Convert.ToInt32(sen_to1.SelectedValue); String Addd_to = Add_to1.Text; }
but its not working i can not go inside loop.
<script type='text/javascript' language='javascript'> function AddNewRecord(keyCode, obj) { if (window.event.keyCode==13 )var grd = document.getElementById('Gridview1'); var tbod=grd.rows[0].parentNode; var newRow=grd.rows[grd.rows.length - 1].cloneNode(true); cleanUpInputs(newRow); tbod.appendChild(newRow); } } return false ;
I would like to enable/disable the field BagNo in my gridview, depending on the value of another field in the gridview called ScriptNo, when I click the edit button I get this message "Object reference not set to an instance of an object".
here is the code
Protected Sub GridView1_RowEditing(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewEditEventArgs) Handles GridView1.RowEditing Dim row As GridViewRow = GridView1.Rows(e.NewEditIndex) If DirectCast(row.FindControl("ScriptType"), TextBox).Text = "TTA" Then
am having a class which contains user defined data type property. I have created an instance of that class. When I bind that object of that class to DetailsView it is showing all properties except user defined data type property. Here is the sample code.
public class Customer public string CustomerName { get; set; } public int Age { get; set; } public Address CustomerAddress { get; set; } } Address class looks like public class Address { [code]...
when we declared as static then we will not create the object to call the static method. then my doubt is how is call the static constructor after creating the object?can you explain cleary?
On Edit Click, the DropDownList in the GridView brings the previously selected value.On Update Click, the error is: "System.FormatException: Input string was not in a correct format."
ddlRegionNavn.DataTextField = "RegionNavn"; ddlRegionNavn.DataValueField = "RegionID"; // from RegionNavn to RegionID
On Edit Click, the DropDownList values in the GridView is not firing and the following error shows.Object reference not set to an instance of an object. How to implement the code when having a value of type Int ?
When I am executing the below code on Visual Studio 2008, then it is executing properly with out any error. But when i am executing it on Visual Studio 2012, then it showing me following error (System.NullReferenceException: Object reference not set to an instance of an object) at line 64
Why is it so?
.vb Code is below :
Imports System.Data.SqlClient Imports System.Data Partial Class grid Inherits System.Web.UI.Page Function constr() As String Dim i As New IO.StreamReader(Server.MapPath("constr.config"))
I have a dropdownlist attached to a cell when edit is selected. I am using the following code to populate the drop down list with the value that is on the row.
dlBU.Items.FindByValue((e.Row.FindControl("lblBU") as Label).Text).Selected = true;
This works famously when I have a value in the cell. It fails when the cell has not yet been populated. Is there an if then clause that if the value of e.Row.findcontrol("lblBU") is null no default value?