C# :: Going Back And Forth Between 2 Forms Show Error Invalid Operation
Jul 29, 2014
So the thing is I have 2 forms, form 1 is displayed first, and form2 would be open when click the next button on form1.
So i was success in moving to the next form, and even getting back to the previous, and then next again, but on the second time I try to go back from form2 to form 1, this error show up.
The error:
Form that is already displayed modally cannot be displayed as a modal dialog box. Close the form before calling showDialog.
I have tried to submit this topic before but i didn't submit my whole code and it was removed. So here it is. All I am trying to do is load form2 from form1 then back to form1 from form2 for a certain number of times the get out of the loop. I am new to C-Sharp and it seems as though I cant seem to figure out a way to do this.
Here is form1 and form2 code. I have commented out a few things I have tried.
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data;
After looking online for a string replace function in C and finding so many examples that go through the entire string twice. First round to find how number of occurances of substitute in string, using that to malloc for a new string to include additional space for replace, then going through the search string again to get all but what's to be substituted out. I feel it's kind of silly to go through the string twice. Therefore, I'm trying to implement my own string replace, that only searches through the string for what's to be substituted, once.
Here is the same code, but with execution + some syntax highlighting: Ideone.com | Online C Compiler & Debugging Tool..It works great, until it gets to grabbing whatever remains in the search string after the last found sub. The realloc throws a runtime error:
Aborted From my understanding, this is from me going outside of the bounds of the heap and using memory I haven't allocated, or using a free'd pointer. I'm not seeing where either of these are happening in my code, and was wondering what the best way to go about figuring out where the error exactly occurs.
The exercise consists on 3 procedures. We get the information from a .txt like these:
01/03/2011 A 02/03/2011 F 03/03/2011 C 04/03/2011 T (...)
Simulating a Videoclub database where the letters stand for the type of movie (A=Action, T=Terror, C=Comedy, ...) and the dates they were rented.
a) How many movies from one specific genre have been rented more than 'n' times? The genre and the value 'n' must be entered by the user.
b) How many movies and which genres belong to a certain date? The date must be entered by the user.
c) Print a list that shows the number of times a movie from each genre has been rented.
So far this is what I've got:
Code: #include <stdio.h> #include <stdlib.h> #include <string.h> #define MAX 100
typedef struct { int dia,mes, any; char genere;
[Code] ....
But right now, my main problem is that I can't even debug because i get an error in line 97 --> while (llista[i][j] != EOF) <-- saying "invalid operands to binary != (have 'lloguer' and 'int').
I've tried to cast (int) before "llista[i][j]" but it says that I'm already supposed to get an integer from that.
class Secure { private: int seconds; bool isRUNNING; public: Secure(int seconds) {
[Code] .....
ERROR:
error C2276: '&' : illegal operation on bound member function expression
I read that due to explicit casting, threads cannot be created within a class. I'm trying to thread a scanning system to relieve stress on my main program/module, rather than having the scanner stunt their performance.
I am using visual studio 2012 on windows 7. but, when I have compiled my programs and run them on an older pc to test out its functions, I receive an error saying that the program is not a "valid win32 application." I have even tested this with a very simple hello world console application, but the problem still remains. Where is the error coming from? is the application corrupted during transport? (upload to internet) or are programs compiled on win 7 incompatible with win xp
The compiler keeps on telling me that invalid conversion from wxBitmap* to wxString on the line with the AddTool function, whiles I do not even try to do such an ambiguous typecast.
wxWidgets 2.9.4 MinGW gdb
Code:
#include "mainwnd.h" //namespaces
//other definitions and declarations CMAINWND::CMAINWND(const wxString& szTitle):wxFrame(NULL,wxID_ANY,szTitle) { wxImage::AddHandler(new wxBMPHandler);
Code: g++ --g -c ErrorH.cpp -o ErrorH.o ErrorH.cpp: In static member function "static ErrorH& ErrorH::Instance()": ErrorH.cpp:9: error: invalid initialization of non-const reference of type "ErrorH&" from a temporary of type "ErrorH" make: *** [ErrorH.o] Error 1
This code works on Windows, how can I get it to work on Linux?
i want to modify value of whole array by passing it to a function and make each value of array multiplied by 3 ,return the value to main and print it using pointer.
error : invalid Lvalue is the error
Code:
#include<stdio.h> main() { int i,arr[10]; for (i=0;i<=9;i++) { printf("Enter value of arr[%d] : ",i); scanf("%d",&arr[i]);
getting an invalid null pointer error message after a successful build. This program is supposed to ask for firstName, lastName, age and maJor and keep doing so until the age that is input is 0 and then the program closes. Here is what I have.
#include <iostream> #include <string> using namespace std;
I've been attempting to design a multiform WFA in Visual Studio 2010, but I'm so rusty with the language it's hard to remember how to do a lot of things, especially when it comes to visual programming, which my class only partially covered. I've never made a multiform application before, and my problem essentially boils down to how to pass data between forms.
My application is a simple item list and order form, sort of mimicking what you might see on a site like Amazon or eBay. My first form contains a drop down list and 'checkout' button. The dropdown list has been populated with an object collection, each object holding the product's name and price.
public partial class Form1 : Form { //Item class for dropdown menu public class Item { public string Name; public decimal Price; public string itemName
[Code] ....
When the 'checkout' button on form 1 is clicked, I want the Price and Name properties of the selected droplist item to appear in a pair of text boxes on form 2 for the purpose of lowering the user's cognitive load (if they can see what they've selected, it's one less thing to remember).
I've seen plenty of tutorials on how to send a textbox Text property between forms, but none for how to do this. As I said, I'm rusty with the language, and I'm pretty sure there's a better way to set up my combobox items, but I can't remember how to set it up.
So form two needs to pass information that was typed in its text box to form 3. So then form 3 can use this information. I think I am creating a new instance of form 2 because I get the exception can not divide by 0 so it is empty even if I typed in a integer in the text boxes. How to pass information from the textbox to a var that can be used in another form.
public partial class MapProperties : Form { private int _numRows; public int NumRows { get { return _numRows; }
I am writing a program in Visual C++ 10 with 2 forms.
In the first form I have a textbox and a button. The button opens the second form.
In the second form, I have a button that changes the text in the textbox in form1 to an item from a listbox in form2.
Here is my problem. When I do the code for the button in form2 to change the textbox in form1 I get the errors:
error C2065: 'textBox1' : undeclared identifier error C2227: left of '->Text' must point to class/struct/union/generic type
I thought maybe I should just include the "Form1.h" file but I can't do that because I already included "Form2.h" in form1 in order to be able to open the second form. If I try to include form1 in form2, it says that the code to open form2 is an error now.
My question is, how can I access identifiers such as "textbox1" from other forms and other files when I already used the first form to open the second form? I also want to know how to do this for all identifiers between all files.
how to print the selecteditem from a listbox into a textbox because that doesn't work by just setting them equal either.
Here is my code:
#pragma once #include "Form2.h" namespace Test1 { using namespace System;
Well I know how to pass values between forms using get and set properties. But the problem with it is everytime I want to pass values from form2 to form1 it doesn't appear. To make it appear I have to type form1.Show(); which open form1 a second time and then show the value. Is there any way I could make it appear without using form1.Show();?
I am currently writing a program which needs an edit form. This form is to edit a country in the datagridview which I have. I am however confused about how to pass the data from the data gridview in the main form to the relative places on the edit form. I have done most of the coding as shown below. I know I need a method in my AVL class to return all the information of the selected country back to the main form method which then passes it back to the edit form and displays it. I am unsure what to pass and what to write in this method.
Main form method
public void button2_Click(object sender, EventArgs e) { // creates new form referencing data grid view and AVL Tree EditCountryForm editform = new EditCountryForm(ref this.countryTree, dataGridView1); string CountryName = ""; //set name of country selected to string
What I'm doing is giving the user the choice to show 2 different dates. 1 in yyyy-mm-dd notation and the other in dd-mm-yyyy notation.
I'm using a second form to do this.
So from Form1 I have my data in the datagrid and in Form2 I have 2 radio buttons giving the user the choice between Date1 and Date2. So how would I be able to interact with the first form with the radio buttons?
I've changed up my code to the retail checkout WFA I am trying to make. I have an item list filled with objects of the now globally accessible 'Item' class, but I'm having trouble.
Essentially, I want to send an object of the item class chosen from a dropdown menu to form2, where I will fill in certain blank attributes with data entered in form2's text boxes and comboboxes. The problem, it seems, is I need another itemlist in form2 that will hold the object being passed to form 2, so I can then pass all the information to textboxes on form3 (the receipt/review page). It's been more than a year since I coded with C#, and I've forgotten quite a bit. I was also not able to find any tutorials on building an item list without an associated combobox or droplist, which is what I need.
This is my item class (minus most of its properties so the page doesn't stretch).
class Item { public string prodName; public string fName; public string lName; public string ccNum; public string ccProv; public string shipAddr;
[code] ....
For anyone who didn't see my last question, I'm in a User Interface Design class, not a C# class. I know this probably isn't the best code out there, but for my purposes the program just needs to compile beginning to end and pass the data like it should.
I'm trying to port a Win32 application over to Windows Forms so that I can have better graphical control over the interface. The program itself is pretty simple; in the main message loop it listens for a WM_CopyData containing a certain char array, and occasionally sends WM_CopyData itself after the user clicks a certain sequence of buttons.
I found a couple of pages discussing how to completely override the Windows Forms WndProc, but I rather like having the framework do all of the control and would prefer to only latch onto it, rather than replace it. So, what would be the best way to have a Win Forms application listen for Windows Messages continuously and execute a function upon receiving them?
If I do need to override WndProc, what is the syntax? I found the following code:
Code:
protected override void WndProc(ref Message m) { base.WndProc (ref m); if (m.Msg==0x4a) // WM_COPYDATA { // do your stuff here... } }
But when I stick that into my main.cpp file right after int main function, "protected" gets highlighted as a syntax error with the message "IntelliSense: expected a declaration".
