bkedersha Posted August 8, 2005 Posted August 8, 2005 (edited) I have a new error on my page. I enter in a new grant, it does not have any budget data. When I click on the tab, this new error comes up. In the application, the user enters in a new Grant. There is in Budget data for the Grant. When a user selects the Budget tab, the page tries to retrieve the Grant's Budget data, but there is none in the table. The previous developer did not understand that with ASP.NET, you cannot get an empty record set. Input string was not in a correct format. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.FormatException: Input string was not in a correct format. Source Error: Line 42: conn.close() Line 43: lblCurrencyName.text = session("CurrencyName") Line 44: select case GrandTotalUSDValue.text > 250000 Line 45: case true Line 46: 'GrandTotalUSDValue.cssclass="ColorUp" Source File: D:\GrantManagementWeb\BudgetDataForm.aspx Line: 44 Stack Trace: [FormatException: Input string was not in a correct format.] Microsoft.VisualBasic.CompilerServices.DoubleType.Parse(String Value, NumberFormatInfo NumberFormat) +195 Microsoft.VisualBasic.CompilerServices.DoubleType.FromString(String Value, NumberFormatInfo NumberFormat) +84 [invalidCastException: Cast from string "" to type 'Double' is not valid.] Microsoft.VisualBasic.CompilerServices.DoubleType.FromString(String Value, NumberFormatInfo NumberFormat) +173 Microsoft.VisualBasic.CompilerServices.DoubleType.FromString(String Value) +7 ASP.BudgetDataForm_aspx.Page_Load(Object Sender, EventArgs e) in D:\GrantManagementWeb\BudgetDataForm.aspx:44 System.Web.UI.Control.OnLoad(EventArgs e) +67 System.Web.UI.Control.LoadRecursive() +35 System.Web.UI.Page.ProcessRequestMain() +750 :confused: Edited August 8, 2005 by bkedersha Quote
Jackpanel Posted August 8, 2005 Posted August 8, 2005 Cast from string "" to type 'Double' is not valid Looks like GrandTotalUSDValue.text is blank. It needs to be a double for your Select Case comparison Quote
bkedersha Posted August 8, 2005 Author Posted August 8, 2005 GrandTotalUSDValue.text is blank because it has no values until a udget is entered GrandTotalUSDValue.text is blank. The user needs to enter in the first budget totals before the text box comes back with a value. Cast from string "" to type 'Double' is not valid Looks like GrandTotalUSDValue.text is blank. It needs to be a double for your Select Case comparison :confused: Quote
Jackpanel Posted August 9, 2005 Posted August 9, 2005 If your textbox is blank, you're going to get an error with this line: select case GrandTotalUSDValue.text > 250000 Its trying to compare "" to 250000 - hence the Cannot Convert "" to Double error. You need to first make sure there is a number in the Grand Total box before checking to see whether its higher than 250000. Try wrapping the Select statement in a : If IsNumeric(GrandTotalUSDValue.text) Then Select Case GrandTotalUSDValue.text > 250000 case true 'GrandTotalUSDValue.cssclass="ColorUp" ' other processing if necessary End Select End If Quote
*Experts* Bucky Posted August 9, 2005 *Experts* Posted August 9, 2005 Actually, the error is occurring because you cannot compare a string and a double (or integer, or any other numeric data type). You could be comparing "moo" > 2500 or "1337" > 2500... obviously it won't work. This is where the static methods of the System.Convert class come into play: If GrandTotalUSDValue.Text.Trim().Length > 0 Then ' Check for a value first Try select case Convert.ToDouble(GrandTotalUSDValue.text) > 250000 ' Convert to double first case true 'GrandTotalUSDValue.cssclass="ColorUp" ' Other cases go here End Select Catch ex as InvalidCastException ' Catch any errors ' Display an error message End Try Else ' No value entered End If I'd also reccomend reading MSDN on Developing a Validator Control Quote "Being grown up isn't half as fun as growing up These are the best days of our lives" -The Ataris, In This Diary
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