Conversion From String "" To Type 'Double' Is Not Valid?
Apr 4, 2011
I have a variable that contains an integer which I then want to save as the value for a column (of type integer in the sql database and int32 in the entity model), but when I try this I receive the error:
"Conversion from string "" to type 'Double' is not valid"
I'm very confused by this since I'm not using a string or a double? The trouble-making line is:
UpdateBed.First.occupant = GetID
And here is the full code snippet:
Private Sub btnReserve_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnReserve.Click Using dbContext As pbu_housingEntities = New pbu_housingEntities ' Check that the room is still available.
Dim hall As String = CStr(Session("hall"))
Dim room As String = CStr(Session("room"))
Dim checkOccupants = From p In dbContext.Rooms [code]....
This code works somewhat, but it won't place all of the text into the textbox.. If I change a few things I get an error where I highlighted the code in red. Conversion from string "" to type 'Double' is not valid. But the code works, like I said somewhat, as you see it, it just doesn't load all of the text to the text box.555632.txt
Code: Public Class Form1 Private Sub OpenFile_Click(sender As Object, e As EventArgs) Handles OpenFile.Click Dim IdxList As String Dim ProgArray() As String Dim Index() As String
Getting this error: Conversion from string "04/07/2010" to type 'Double' is not valid. ---> System.FormatException: Input string was not in a correct format.
Using cmdUpdate As New SqlCommand With cmdUpdate .Connection = onyxConnection .CommandType = CommandType.StoredProcedure[code]....
I keep getting this error when attempting to execute this code, even after placing a CType around the value and defining it as double?Private Sub GridView1_RowDeleting(sender As Object, e As System.Web.UI.WebControls.GridViewDeleteEventArgs) Handles GridView1.RowDeleting' The deletion of the individual row is automatically handled by the GridView.
I am wishing to retrive picture stored in sql server database to web form using gridview control. I have created a Handler.ashx file with following coding:
[Code]....
And in the aspx page I am calling this as:
[Code]....
But when I am executing this project, it prompts following error:
I have a FormView that allows a user to register for a company event. I want to do a couple of things with this form.
1. I need to write this data to a MS SQL database
2. I need to send an email confirmation of their registration to their email.
I know how to do both of these things, but i am having trouble doing both at the same time.
It would be nice if I could do it in one click, but I coded it into two pages to try to help simplify it.
The first page allows the user to input their information into a formview and when they click the submit button, it places those answers into session variables:
[Code]....
[Code]....
The Second page confirms the users information by taking those session variables and placing them into labels:
[Code]....
[Code]....
However, after I place information into the formview on the first page, it throws up this error:
"Conversion from type 'TextBox' to type 'String' is not valid".
I have a gridview which I'm trying to get the display of phonenumbers listed in a certain display format; (xxx) xxx-xxxx.If I have the code such as this, it displays the unformatted phone number and (000) 000-0000 for the null items.
Conversion from type 'DBNull' to type 'String' is not valid
Dim OledbString As String = ("SELECT Product_Hierarchy,Model,Origin,Item_Code,Description,Price_USD FROM [sheet1$]") 'Dim eAdapter As New SqlDataAdapter(sqlString, connection) Dim eAdapter As New OleDbDataAdapter(OledbString, connection) Dim eTable As New DataTable() eAdapter.Fill(eTable) Dim i As Integer = 0 [code]...
I have a web in ASP.NET AND CODE IN VB MY DATABASE IS ACCESS WHICH WAS CREATED INITIALLY AND OLD DATA IS ACCESSED FROM THIS ACCESS DATABASE.
THE PROBLEM IS WHEN THE FIELD IS BLANK THE FOLLOWING ERROR COMES
Conversion from type 'DBNull' to type 'String' is not valid.
MY CODE IS AS UNDER
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubmit.Click Dim PNO As String = inputtxt.Text Dim connectString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=C:awingAWing.mdb" Dim con As OleDbConnection = New OleDbConnection(connectString) con.Open() Dim qstr As String qstr = "select * from PersData where PNO='" + inputtxt.Text + "'"
Im receiving a strange error Error Message: Conversion from string "15/08/2010 22:21:35" to type 'Date' is not valid.
I know this is generally down to cultural date formats etc, however the reason this is strange is it just randomly occured twice in the last week, the website has been running since october and nothing has changed,
The error constantly occured until the IIS was reset and recompilled the site, its been running fine since, however im just trying to figure out what could cause such an error to occur.
Sub btnAdd_Click(sender As Object, e As EventArgs) 'converting datatypes to integer Dim insertB As Integer Dim insertA As Integer Dim cat As Integer cat = ddl.SelectedItem.Value
This is all in the Code Behind under the Page Load function.
Basically, I'm trying to convert an ASP page into ASP.NET. I've worked with ASP and PHP a lot more than I have with ASP.NET and I'm just having trouble with the syntax.
I get the error - Conversion from type 'DBNull' to type 'Integer' is not valid. - on the line.....
Dim newid As Integer = e.Command.Parameters("@latestRowId").Value.........in vb code behind.
I have the identical code for another page with the exception of the field names and it works fine. The only thing I did differently, as far as I know, is I copied the asp and code behind from the page that works into this page and manually changed the field and table names. I don't know what the problem is. Does anyone see any problems?
I seem to be having issues with posting forms with DropDownLists. I've looked all over the net and tried various solutions, but none seem to work for me.
I'm getting the following error: The parameter conversion from type 'System.String' to type 'Models.Organization' failed because no type converter can convert between these types.
Here's my ViewModel:
[Code]....
Here's my controller:
[Code]....
The objects are generated by ADO.NET Entity Framework. Organizations is its own object, but also a property of Profile (each user belongs to one organization). Now I understand what the error message is saying, just not sure how else I'm supposed to do this.
I am getting an error when attempting to call a stored proc from my asp.net page.
e.Message = "Conversion failed when converting character string to smalldatetime data type."
The stored proc is being called by:
The asp.net code that is calling the stored proc is:
//Display search results in GridView; SqlConnection con = new SqlConnection(strConn); //string sqlItemSearch = "usp_Item_Search"; SqlCommand cmdItemSearch = new SqlCommand(sqlItemSearch, con);
I am LINQ querrying against a datatable. However, I am unsuccessfull with catching null values. Here is my code that is giving me the following error.
[Code]....
I am checking to see if minperc is null. However to check that it still is trying to convert the value to double. Cant figure out a way around it. Here is the error: Cannot cast DBNull.Value to type 'System.Double'. Please use a nullable type.
I am getting some float values in front end from back end.For example suppose I get 7.770000 the through convert.double I am converting it into 7.77.This is perfectly fine.But when I have 0.00005 then convert.double is displaying it like 5E-05, which is not fine.
I am currently developing an iPhone app that will work as a security check-in system for events at a church. The main goal is to be able to search a pre existing MS SQL database for a participant, and then save them to a list on the iPhone/iPod Touch/iPad. Easy enough. One of the fields in the MS SQL database is of Image data type, and its function is to store the participant's image in binary form. I currently am not allowed to switch to varbinary(MAX). From the iPhone, I use:
You may be wondering what the base64StringFromData is. It's a category discussed here, Any base64 library on iphone-sdk? In the category, it returns a string as NSASCIIStringEncoding. I then send that string to a Visual Basic web service using POST. Assume in the following that I have already set up and opened my SQL connection, and initlialized a SQL Data adapter and command. So the function looks similar to this:
Public Function sendCommand(ByVal image As String) As String Dim commandString As String commandString = "insert into phoneApp(image) values(@image)" Dim encoding As New System.Text.UTF8Encoding sqlDataAdapter.InsertCommand = (commandString, sqlConnection) sqlDataAdapter.InsertCommand.Parameters.Add(@"image", SqlDbType.Image, image.length).Value = encoding.GetBytes(image) sqlDataAdapter.ExecuteNonQuery() End Function
Now, finally, here's what is happening. In another function, I call Response.BinaryWrite(SqlDataReader.Item("image")). In Internet Explorer, doing this would then make the image appear in the browser. Instead, it displays the string in base64 form. Copy and pasting that string in a base64 converter off the net, and it works. So the encoding on the iPhone did encode to base64 properly. Here's the question. Do I even need to be encoding to base64 to save into Image Data Type, or should I be focusing on learning how to encode the NSData into a different binary string?
I am trying to get text box values into a database from a asp.net form. In my SQL server database I have defined the field emailID as nvarchar(50) and I still get the error messageconversion failed when converting the varchar value abcd@efg.com to type int" I am not trying to convert it int so my guess is SQL server is doing some kind of implicit conversion.
