C# bound table adapter not updating until called twice - c#

New to C# from vb.net and I am just making some mock bound applications for now. I have problems with the following code. If I pic an image and exit the application, there is no change. Even if I move a row. However if I upload an image, move to another row, then add another image. After exiting the application the first image will be there but not the second.
In short I have to attempt to upload to another record before the record I actually want updating will do so.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
namespace DBUserManagement
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'dsUsers.Users' table. You can move, or remove it, as needed.
this.usersTableAdapter.Fill(this.dsUsers.Users);
}
private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{
OpenFileDialog ofd = new OpenFileDialog();
if (DialogResult.OK == ofd.ShowDialog())
{
imgUser.SizeMode = PictureBoxSizeMode.StretchImage;
imgUser.Image = new Bitmap(ofd.OpenFile());
//update bound field.
usersTableAdapter.Update(dsUsers);
}
}
}
}
Any ideas on what I am missing or not understand correctly? Any help appreciated.
/P

The answer was I needed to call the BindingSource's .EndEdit(); method.
So I am guessing it was down to the binding source still having hold of something.
Seems like I'm on the right track anyhow, I looked up the details on MSDN :)

Related

Awesomium "LoadingFrameComplete" is firing too many times

Just recently began tinkering with Awesomium, it's very cool and much better than the stock webBrowser for WinForms.
However, when I use the _LoadingFrameComplete method to determine if the page has loaded, it seems to be firing 10+ times (when used on Facebook, 2 times when navigating to google.com)
I am trying to get the comparable method of webBrowser1_DocumentCompleted (which only fires one time, after the document has completed).
Is this a 'me' problem, or am I using the wrong methods to check whether the website has finished loading completely.
I'm using Visual C# 2010 Edition
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Debugging_Problems
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
string searchURL = textBox1.Text;
webControl1.Source = new Uri(searchURL);
}
private void Awesomium_Windows_Forms_WebControl_LoadingFrameComplete(object sender, Awesomium.Core.FrameEventArgs e)
{
richTextBox1.AppendText("Completed.\n");
}
}
}
You need to use IsMainFrame
private void Awesomium_Windows_Forms_WebControl_LoadingFrameComplete(object sender, Awesomium.Core.FrameEventArgs e)
{
if (e.IsMainFrame)
{
richTextBox1.AppendText("Completed.\n");
}
}
Try putting if(e.IsMainFrame) { .... } inside your LoadingFrameComplete event handler and only put your code in there. – Jon
That was the answer. Thank you.

check for duplicate on lose focus in datagridview

I am trying to write a data input app using Visual Studio 2017 C# for my company.
We have 2 tables, SI and SIC, in a SQL DB.
I have created a form and put a bound datagridview, which is bound to the SIC table.
On form load, it shows all data nicely.
What we want to do is enter data into this datagridview and save.
However, when entering a value into column D, we want to check that it doesn`t exist in column D in the SI table.
I did have it setup with a unique constraint, however, when the record wasn`t unique, an error message appeared, and pressing OK would delete all the other data on the row. Not desirable as there is quite a lot of data to be entered.
I am very new to programming in general, so would appreciate any advice that could be given.
My form code looks like this:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Product_List
{
public partial class NewProduct_frm : Form
{
public NewProduct_frm()
{
InitializeComponent();
}
private void NewProduct_frm_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'bHTESTDataSet.SIC' table. You can move, or remove it, as needed.
this.TableAdapter.Fill(this.bHTESTDataSet.SIC);
}
private void Save_btn_Click(object sender, EventArgs e)
{
this.Validate();
this.BindingSource.EndEdit();
this.tableAdapterManager.UpdateAll(this.bHTESTDataSet);
}
private void Reload_btn_Click(object sender, EventArgs e)
{
this.TableAdapter.Fill(this.bHTESTDataSet.SIC);
}
}
}

How to use event handlers in C#

I created a form with just 2 textboxes and a button. In the first one I type a temperature in Fahrenheit and when I press the button "Convert", the program calculates and puts the temperature in Celsius in the other TextBox. It's working fine.
Now I want the program to clear the second TextBox when I start typing in the first TextBox. Below I show just a part of the code, which didn't work. Can anybody help me?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Conv_Temp
{
public partial class Frm_Principal : Form
{
public Frm_Principal()
{
InitializeComponent();
}
public event EventHandler Leave;
private void Tb_Temp_Leave(object sender, EventArgs e)
{
MessageBox.Show("Leaving TB Tb_Temp");
Tb_Result.Text="";
}
}
}
I think you are almost there.
Try adding this under InitializeComponent();
this.Tb_Temp.TextChanged += new System.EventHandler(this.Tb_Temp_Leave);
Add new Event handler in your form designer code.
this.textBox1.TextChanged += new System.EventHandler(this.ModifyTextBox1);
and implement this event in above form.cs file(Form_Principal )
private void ModifyTextBox1(object sender, EventArgs e)
{
textBox2.Text = String.Empty;
}
Please follow good convention for writing codes this is just a demo.

FileDialogue - Apparently it doesn't work?

I am currently trying to make my mp3 player for a project.
I have written this code by following a guide:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
string[] files, path;
[STAThread]
private void button1_Click(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
files = openFileDialog1.SafeFileNames;
path = openFileDialog1.FileNames;
for (int i = 0; i < files.Length; i++)
{
listBox1.Items.Add(files[i]);
}
}
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
axWindowsMediaPlayer1.URL = path[listBox1.SelectedIndex];
}
}
}
And heres a screen of my form:
For some reason when I click the OPEN button, nothing happens. First when I used this code I got an error about "Form1_load", but since I wasn't using this, I just deleted the error line and then there was no errors found.
I am very clueless, so anyone with ANY idea what is wrong?
I followed this guide completely:
http://www.c-sharpcorner.com/UploadFile/8ea152/mp3-media-player-in-C-Sharp-4-0/
Thanks
First of all make sure that you have assigned click event for your button for that just double click on your button from design window if it redirects you to the buttonclick method then everything is fine and if it does not then assign it first. For that
public Form1()
{
InitializeComponent();
button1.Click += button1_Click;
}
And
Why do you require [STAThread] here? I mean just remove the attribute and try again because [STAThread] is used for below reson:-
The STAThreadAttribute marks a thread to use the Single-Threaded COM
Apartment if COM is needed. By default, .NET won't initialize COM at
all. It's only when COM is needed, like when a COM object or COM
Control is created or when drag 'n' drop is needed, that COM is
initialized. When that happens, .NET calls the underlying
CoInitializeEx function, which takes a flag indicating whether to join
the thread to a multi-threaded or single-threaded apartment.
For more information :-
http://blogs.msdn.com/b/jfoscoding/archive/2005/04/07/406341.aspx

How to move form box to a new location

I have a windows form project, and I want the whole form to change location automatically, but the truth is that I have no idea what to call, and where to call it. I have searched online, and all code I discovered was incomplete. I am fairly new at this, so it did not help me.
Here is the code that I am working with, if it helps:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Media;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
private SoundPlayer _soundplayer;
public Form1()
{
InitializeComponent();
SoundPlayer player = new SoundPlayer(Properties.Resources.sound);
player.Play();
}
private void pictureBox1_Click(object sender, EventArgs e)
{
var myForm = new Form2();
myForm.Show();
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
_soundplayer.PlayLooping();
}
}
}
Change the Location for the form:
this.Location = new Point(400, 500);
You just need to decide which event will trigger this code; for example, the Click event of a button.
MSDN: Location
To position forms using the Properties window
In the Properties window, choose the form from the drop-down. Set the form's StartPosition property to Manual.
Type the values for the Location property, separated by a comma, to position the form, where the first number (X) is the distance from the left border of the display area and second number (Y) is the distance from the upper border of the display area.
Note Expand the Location property to enter the X and Y subproperty values individually.
Reference MSDN

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