I have a RichTextBox in a C# project. Adding characters and counting the number of characters per line works.
The issue comes when I try to delete characters with the Backspace Key
I have commented out the code I have tried while pressing the Backspace Key
I also tried to use a KeyPress event to manage counting characters deleted complete fail.
If anyone would like to test the code here are the properties of the RichTextBox Name rtbInfo.
Size 347 by 120 Font 10.8 Bold WordWrap False NO Scroll Bars Max Length 135
GOAL Increase the variable res by 1 for each character or space deleted with the press of the Backspace Key.
I would prefer to not use KeyPress KeyUp or KeyDown Events if at all possible.
Happy to consider code suggestions with those Event designs.
public partial class frmRTB : Form
{
int Count = 0;
int Lines = 0;
int cT = 0;
int res = 0;
public frmRTB()
{
InitializeComponent();
//rtbInfo.KeyPress += rtbInfo_KeyPress;
/*=== This Must be here to register rtbInfo ===*/
/*=============================================*/
}
private void frmRTB_Load(Object sender, EventArgs e)
{
ActiveControl = rtbInfo;
}
/*private void rtbInfo_KeyPress(object sender, KeyPressEventArgs e)
{
if (rtbInfo.TextLength == 0)
{
tbMessage.Text = "Nothing to Delete";
return;
}
if (e.KeyChar == ((char)Keys.Back) & (char.IsControl('\b')))
{
//rtbInfo.Text = rtbInfo.Text.Remove(rtbInfo.TextLength - 1, 0);
//rtbInfo.Select(rtbInfo.TextLength - 0, 0);
//rtbInfo.ScrollToCaret();
//cT = cT - 1;
//res = - 1;// Last edit was res - cT ?
//tbCount.Text = "Back Fire";
//e.Handled = true;
}
}*/
public void rtbInfo_TextChanged(Object sender, EventArgs e)
{
Count = rtbInfo.TextLength;
Lines = rtbInfo.Lines.Length;
foreach (char chr in rtbInfo.Text)
{
if (char.IsLetterOrDigit(chr))
{
cT = cT + 1;
res = 33 - cT;
}
/*
Regex regex = new Regex(#"^[\b]+$");
//Regex regex = new Regex(#"^[\b\S\t\D\W]+$");
if (regex.IsMatch(rtbInfo.Text))
{
tbCount.Text = "Use BACKSPACE Key to Edit";
}*/
//if (chr == '\b')
//if (chr == ((char)Keys.Back))
// tried above if statments they do not fire
// This fires when any key is entered NOT just the Backspace key
/*if (char.IsControl('\b'))// & !(char.IsLetterOrDigit(chr)))
{
//rtbInfo.Text = rtbInfo.Text.Remove(rtbInfo.TextLength - 1, 0);
//rtbInfo.Select(rtbInfo.TextLength - 0, 0);
//rtbInfo.ScrollToCaret();
res = +1;
tbCount.Text = "Use BACKSPACE Key to Edit";
}*/
if (Lines == 5 | Count == 135)
{
rtbInfo.ReadOnly = true;
}
if (rtbInfo.ReadOnly == true)
{
txtBoxMsg.Text = "";
tbMessage.Text = "";
tbCount.Text = "Use BACKSPACE Key to Edit";
}
if (rtbInfo.Text.EndsWith("\n"))
{
cT = 0;
res = 0;
}
if (cT == 33)
{
SendKeys.Send("{ENTER}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
cT = 0;
res = 0;
}
if (rtbInfo.ReadOnly == true)
{
string message = "Press YES to edit Notes" + '\n' + " NO Clear Notes";
string title = "Edit Notes";
MessageBoxButtons buttons = MessageBoxButtons.YesNo;
DialogResult result = MessageBox.Show(message, title, buttons);
if (result == DialogResult.Yes)
{
rtbInfo.ReadOnly = false;
SendKeys.Send("{BACKSPACE}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
cT = 0;
res = 0;
}
else
{
rtbInfo.ReadOnly = false;
rtbInfo.Clear();
tbCount.Text = "All Notes Remove";
}
}
if (res == 0)
{
res = 33;
}
txtBoxMsg.Text = "Total of " + (135 - Count) + " can be entered & " + (5 - Lines) + " Lines";
tbMessage.Text = "Total of " + res + " more char can be entered on line " + Lines;
//tbCount.Text = "Count is " + Count + " cT " + cT + " res " + res;// For Testing
return;
}
I solved this using both TextChanged & KeyPress events
While that solution worked I decided to put all the code in a KeyPress event ONLY.
One HUGE mistake in my original question was in InitializeComponent
Look up and read when & how to use this method. Enjoy the Code
public partial class frmKPO : Form
{
int rtbTotLen;
int linesTot;
int lineNum;
int res1;
int count1;
int res2;
int count2;
int res3;
int count3;
int res4;
int count4;
public frmKPO()
{
InitializeComponent();
}
private void rtbInfo_KeyPress(object sender, KeyPressEventArgs e)
{
rtbTotLen = rtbInfo.TextLength;
linesTot = rtbInfo.Lines.Length;
lineNum = (5 - linesTot);
txtBoxMsg.Text = "Total of " + (135 - rtbTotLen) + " can be entered on " + (5 - lineNum) + " Lines";
if (e.KeyChar == (char)Keys.Back)
{
if (lineNum == 1)
{
--res1;
}
if (lineNum == 2)
{
--res2;
}
if (lineNum == 3)
{
--res3;
}
if (lineNum == 4)
{
--res4;
}
}
else
{
if (lineNum == 1)
{
++res1;
}
if (lineNum == 2)
{
++res2;
}
if (lineNum == 3)
{
++res3;
}
if (lineNum == 4)
{
++res4;
}
}
if (lineNum == 4)
{
count4 = 33 - res4;
tbMessage.Text = "Total of " + count4 + " more char can be entered on line " + (5 - lineNum) + "";
if (count4 == 0)
{
SendKeys.Send("{ENTER}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
}
}
else if (lineNum == 3)
{
count3 = 33 - res3;
tbMessage.Text = "Total of " + count3 + " more char can be entered on line " + (5 - lineNum) + "";
if (count3 == 0)
{
SendKeys.Send("{ENTER}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
}
}
else if (lineNum == 2)
{
count2 = 33 - res2;
tbMessage.Text = "Total of " + count2 + " more char can be entered on line " + (5 - lineNum) + "";
if (count2 == 0)
{
SendKeys.Send("{ENTER}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
}
}
else if (lineNum == 1)
{
count1 = 33 - res1;
tbMessage.Text = "Total of " + count1 + " more char can be entered on line " + (5 - lineNum) + "";
if (count1 == 0)
{
SendKeys.Send("{ENTER}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
}
}
if (linesTot == 5 | rtbTotLen == 135)
{
rtbInfo.ReadOnly = true;
}
if (rtbInfo.ReadOnly == true)
{
txtBoxMsg.Text = "";
tbMessage.Text = "";
tbCount.Text = "Use BACKSPACE Key to Edit";
}
if (rtbInfo.ReadOnly == true)
{
txtBoxMsg.Text = "";
tbMessage.Text = "";
tbCount.Text = "Use BACKSPACE Key to Edit";
string message = "Press YES to edit Notes" + '\n' + " NO Clear Notes";
string title = "Edit Notes";
MessageBoxButtons buttons = MessageBoxButtons.YesNo;
DialogResult result = MessageBox.Show(message, title, buttons);
if (result == DialogResult.Yes)
{
rtbInfo.ReadOnly = false;
SendKeys.Send("{BACKSPACE}");
rtbInfo.ScrollToCaret();
rtbInfo.Focus();
}
else
{
rtbInfo.ReadOnly = false;
rtbInfo.Clear();
tbCount.Text = "All Notes Remove";
}
}
}
private void btnToStart_Click(object sender, EventArgs e)
{
Close();
frmStart fS = new frmStart();
fS.Show();
}
private void frmKPO_Load(object sender, EventArgs e)
{
ActiveControl = rtbInfo;
tbMessage.Text = "Total of " + 33 + " more char can be entered on line " + 1 + "";
}
}
Related
I am trying to use "Anviz Original SDK"
i added simple looping to connect multiple devices.
it was running okay if i only run it for 1 times, but in the second (sometimes the third) it keep crashing and showing erorr "Access Violation" at the output box of Visual Studio.
I've read some posts here on stackoverflow which suggest that there might be a bad pointer somewhere, but i cannot find where. I think My pointers are not corrupt.
The DLL Import for the function are using this code:
[DllImport("tc-b_new_sdk.dll")]
here is the function to loop and connect to device:
private void pictureBox3_Click(object sender, EventArgs e)
{
foreach (ListViewItem item in listViewDevice.Items)
{
if (item.Selected)
{
//int result = connectDevice(item.SubItems[3].Text, "5010");
int ret = 0;
byte[] Ipstr = new byte[16];
//string_to_byte(this.Add_dev_Ip.Text,Ipstr, (byte)Add_dev_Ip.Text.Length);
Ipstr = System.Text.Encoding.Default.GetBytes(item.SubItems[3].Text);
int Port = Convert.ToInt32("5010");
ret = AnvizNew.CCHex_ClientConnect(anviz_handle, Ipstr, Port);
}
}
}
and here is the Timer Tick function to get the data:
private void timer1_Tick(object sender, EventArgs e)
{
try
{
int ret = 0;
int[] Type = new int[1];
int[] dev_idx = new int[1];
IntPtr pBuff;
int len = 32000;
pBuff = Marshal.AllocHGlobal(len);
while (true)
{
if (anviz_handle == IntPtr.Zero)
{
break;
}
ret = AnvizNew.CChex_Update(anviz_handle, dev_idx, Type, pBuff, len);
//dbg_info("Update~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
if (ret > 0)
{
dbg_info("Msg Type : " + Type[0]);
switch (Type[0])
{
case (int)AnvizNew.MsgType.CCHEX_RET_DEV_LOGIN_TYPE:
{
AnvizNew.CCHEX_RET_DEV_LOGIN_STRU dev_info;
dev_info = (AnvizNew.CCHEX_RET_DEV_LOGIN_STRU)Marshal.PtrToStructure(pBuff, typeof(AnvizNew.CCHEX_RET_DEV_LOGIN_STRU));
string info_buff = "Dev Login --- [MachineId:" + dev_info.MachineId
+ " Version:" + byte_to_string(dev_info.Version)
+ " DevType:" + byte_to_string(dev_info.DevType)
+ " Addr:" + byte_to_string(dev_info.Addr)
+ "]";
//log_add_string(info_buff + " " + dev_info.DevTypeFlag.ToString());
log_add_string(info_buff + " " + Convert.ToString(dev_info.DevTypeFlag, 16));
ListViewItem foundItem = null;
if (foundItem == null)//just test has machineid
{
int i = 0;
for (i = 0; i < listViewDevice.Items.Count; i++)
{
foundItem = this.listViewDevice.Items[i];
if (foundItem.SubItems[1].Text.ToString() == dev_info.MachineId.ToString() && Convert.ToInt32(foundItem.Text.ToString()) != dev_info.DevIdx)
{
foundItem.Text = dev_info.DevIdx.ToString();
break;
}
else
{
}
//foundItem.Text = dev_info.DevIdx.ToString();
foundItem = null;
}
}
DevCount++;
//DevTypeFlag.Add(dev_info.DevIdx, (int)dev_info.DevTypeFlag);
}
break;
case (int)AnvizNew.MsgType.CCHEX_RET_DEV_LOGIN_CHANGE_TYPE:
{
AnvizNew.CCHEX_RET_DEV_LOGIN_STRU dev_info;
dev_info = (AnvizNew.CCHEX_RET_DEV_LOGIN_STRU)Marshal.PtrToStructure(pBuff, typeof(AnvizNew.CCHEX_RET_DEV_LOGIN_STRU));
string info_buff = "Login Change --- [MachineId:" + dev_info.MachineId
+ " Version:" + byte_to_string(dev_info.Version)
+ " DevType:" + byte_to_string(dev_info.DevType)
+ " Addr:" + byte_to_string(dev_info.Addr)
+ "]";
log_add_string(info_buff + " " + Convert.ToString(dev_info.DevTypeFlag, 16));
//log_add_string(info_buff + " " + dev_info.DevTypeFlag.ToString());
//DevTypeFlag[dev_info.DevIdx] = (int)dev_info.DevTypeFlag;
}
break;
case (int)AnvizNew.MsgType.CCHEX_RET_DEV_LOGOUT_TYPE:
{
AnvizNew.CCHEX_RET_DEV_LOGOUT_STRU dev_info;
dev_info = (AnvizNew.CCHEX_RET_DEV_LOGOUT_STRU)Marshal.PtrToStructure(pBuff, typeof(AnvizNew.CCHEX_RET_DEV_LOGOUT_STRU));
string info_buff = "Dev Logout --- [MachineId:" + dev_info.MachineId
+ " Version:" + byte_to_string(dev_info.Version)
+ " DevType:" + byte_to_string(dev_info.DevType)
+ " Live:" + dev_info.Live
+ " Addr:" + byte_to_string(dev_info.Addr)
+ "]";
log_add_string(info_buff);
DevCount--;
ListViewItem foundItem = null;
if (foundItem == null)//just test has machineid
{
int i = 0;
for (i = 0; i < listViewDevice.Items.Count; i++)
{
foundItem = this.listViewDevice.Items[i];
if (foundItem.SubItems[1].Text.ToString() == dev_info.MachineId.ToString() && Convert.ToInt32(foundItem.Text.ToString()) == dev_info.DevIdx)
{
break;
}
foundItem = null;
}
}
//ListViewItem foundItem = this.listViewDevice.FindItemWithText(dev_info.MachineId.ToString(), false, 0);
if (foundItem != null)
{
// DevTypeFlag.Remove(dev_idx[0]);
foundItem.Text = "0";
//this.listViewDevice.Items.Remove(foundItem);
}
}
break;
}
}
else if (0 == ret)
{
//MY_SLEEP(10);
//Marshal.FreeHGlobal(pBuff); // free the memory
break;
}
else if (0 > ret)
{
//buff to small
len = len * 2;
Marshal.FreeHGlobal(pBuff);
pBuff = Marshal.AllocHGlobal(len);
}
else
{
//没有找到消息类型
//Marshal.FreeHGlobal(pBuff); // free the memory
break;
}
//Marshal.FreeHGlobal(pBuff); // free the memory
}
//Marshal.FreeHGlobal(buff_fin);
Marshal.FreeHGlobal(pBuff); // free the memory
}
catch (Exception ex)
{
dbg_info("Error " + ex.Message);
}
}
Really appreciate for any helps.
Thanks.
I made a c# project that lists certain things in ListViews, but the ListViewsare a little annoying, they don't work everytime, sometimes the input is correct and can be displayed in a MessageBox or ListBox but nothing happens when trying to add it to the ListBox, this is my code right now and nothing happens when pressing the button.
private async void button2_Click(object sender, EventArgs e)
{
if(shouldirefresh == true)
{
button2.Enabled = false;
checkBox1.Enabled = false;
checkBox2.Enabled = false;
checkBox3.Enabled = false;
checkBox4.Enabled = false;
checkBox5.Enabled = false;
checkBox6.Enabled = false;
pictureBox1.Visible = true;
webBrowser1.Refresh();
await td(3500);
}
checkBox1.Text = "Highlight -50%";
checkBox2.Text = "Highlight 100%";
checkBox3.Text = "Highlight 50%";
pictureBox1.Visible = true;
min50 = 0;
max100 = 0;
eq50 = 0;
listView1.Items.Clear();
listBox1.Items.Clear(); listBox2.Items.Clear(); listBox3.Items.Clear(); listBox4.Items.Clear();
lsttit.Clear(); lstpoint.Clear(); lstmaxwosl.Clear(); lstmax.Clear();
HtmlDocument doc = this.webBrowser1.Document;
doc = webBrowser1.Document;
var links = PulseVar.myrodoc.GetElementsByTagName("td");
foreach (HtmlElement link in links)
{
if (link.GetAttribute("className") == "title")
{
lsttit.Add(link.InnerText);
}
else if (link.GetAttribute("className") == "point" || link.GetAttribute("className") == "point tekort")
{
lstpoint.Add(link.InnerText);
}
else if (link.GetAttribute("className") == "max" || link.GetAttribute("className") == "max tekort")
{
string RM = link.InnerText.Remove(0, 1);
lstmax.Add(RM);
}
else if (link.GetAttribute("className") == "date")
{
datez.Add(link.InnerText);
}
else if(link.GetAttribute("className") == "average")
{
lstav.Add(link.InnerText);
}
else if(link.GetAttribute("className") == "comment")
{
if(link.InnerText == " ")
{
lstcomment.Add(" ");
}
else
{
lstcomment.Add(link.InnerText);
}
}
else if(link.GetAttribute("className") == "TeacherTitle")
{
this.Text = "Myro ~ " + link.InnerText;
}
}
for (int i = 0; i <= lsttit.Count - 1; i++)
{
ListViewItem d = new ListViewItem(lsttit[i]);
try
{
if (decimal.Parse(lstpoint[i]) < (decimal.Parse(lstmax[i]) / 2))
{
min50++;
d.SubItems.Add(lstpoint[i] + "/" + lstmax[i]);
if (checkBox1.Checked == true)
{
d.ForeColor = Color.Red;
}
}
else if (decimal.Parse(lstpoint[i]) == (decimal.Parse(lstmax[i])))
{
//listView2.Items.Add(lstpoint[i] + "/" + lstmax[i]);
d.SubItems.Add(lstpoint[i] + "/" + lstmax[i]);
if (checkBox2.Checked == true)
{
d.ForeColor = Color.Green;
}
max100++;
}
else if (decimal.Parse(lstpoint[i]) == (decimal.Parse(lstmax[i]) / 2))
{
//listView2.Items.Add(lstpoint[i] + "/" + lstmax[i]);
d.SubItems.Add(lstpoint[i] + "/" + lstmax[i]);
if (checkBox3.Checked == true)
{
d.ForeColor = Color.Yellow;
}
eq50++;
}
else
{
d.SubItems.Add(lstpoint[i] + "/" + lstmax[i]);
//listView2.Items.Add(lstpoint[i] + "/" + lstmax[i]);
}
}
catch (Exception)
{
//listView2.Items.Add(lstpoint[i] + "/" + lstmax[i]);
d.SubItems.Add(lstpoint[i] + "/" + lstmax[i]);
}
d.SubItems.Add(datez[i]);
d.SubItems.Add(lstav[i] + "/" + lstmax[i]);
d.SubItems.Add(lstcomment[i]);
listView1.Items.Add(d);
}
checkBox1.Text += "(" + min50.ToString() + ")";
checkBox2.Text += "(" + max100.ToString() + ")";
checkBox3.Text += "(" + eq50.ToString() + ")";
pictureBox1.Visible = false;
//groupBox1.Location = new Point(12, 12);
checkBox5.Checked = false;
button2.Enabled = true;
checkBox1.Enabled = true;
checkBox2.Enabled = true;
checkBox3.Enabled = true;
checkBox4.Enabled = true;
checkBox5.Enabled = true;
checkBox6.Enabled = true;
shouldirefresh = true;
label3.Text = DateTime.Now.ToString("dd/MM/yyyy hh:mm");
}
Again if I do MessageBox.Show(lsttit[i]); it shows the correct data everytime, my ListView has the correct columns and is set to details but nothing happens at all....
what's wrong here?
I understand that when Thread.Sleep is being executed, the buttons on my GUI are not able to be clicked on.
Is there any other ways to delay my codes from flowing yet still able to click on my buttons on the GUI?
For example right now after my codes execute Thread.Sleep(10000); and within this 10 seconds i'm not able to click on my button1 event, is there anyway that I can still click on my button1 event within these 10 seconds?
private void displaydata_event2(object sender, EventArgs e)
{
txt_data.AppendText(in_data + "\n");
string inStr;
inStr = in_data;
//MessageBox.Show(inStr.Length.ToString());
if (inStr.Length == 12)
{
int indexOfSpace = inStr.IndexOf(' ');
string Patient = inStr.Substring(indexOfSpace + 1);
int rx = 0;
int selected = 0;
txtData1.Text = Patient;
rx = Convert.ToInt16(Patient);
selected = Convert.ToInt16(txt_pnorec.Text);
if (rx != selected)
{
MessageBox.Show("Please check patient settings");
}
}
else if (inStr.Length == 24)
{
label2.Text = "Patient is not selected!";
label2.BackColor = Color.Red;
}
else if (inStr.Length == 10)
{
int indexOfSpace = inStr.IndexOf(':');
string Temp = inStr.Substring(indexOfSpace + 1);
txtData2.Text = Temp;
double tempflo;
tempflo = Convert.ToDouble(Temp);
if (tempflo > 20)
{
lbl_temp.Text = "Fever";
lbl_temp.BackColor = Color.Red;
}
}
else if (inStr.Length == 9)
{
int indexOfSpace = inStr.IndexOf(':');
string ECG = inStr.Substring(indexOfSpace + 1);
txtData3.Text = ECG;
}
else if (inStr.Length == 19 || inStr.Length == 20)
{
int indexOfSpace = inStr.IndexOf(':');
string Systolic = inStr.Substring(indexOfSpace + 1);
txtData4.Text = Systolic;
}
else if (inStr.Length == 21 || inStr.Length == 22)
{
int indexOfSpace = inStr.IndexOf(':');
string Diastolic = inStr.Substring(indexOfSpace + 1);
txtData5.Text = Diastolic;
}
else if (inStr.Length == 16)
{
int indexOfSpace = inStr.IndexOf(':');
string Pulse = inStr.Substring(indexOfSpace + 1);
txtData6.Text = Pulse;
}
else if (inStr.Length == 23 || inStr.Length == 17 || inStr.Length == 27 || inStr.Length == 30 || inStr.Length == 35 || inStr.Length == 29)
{
lbl_bp.Text = inStr;//to display status of BP (Normal,prehypotension etc)
string bp;
bp = inStr;
if (bp.Length == 23 || bp.Length == 27 || bp.Length == 31 || bp.Length == 35 || bp.Length == 30)
{
lbl_bp.BackColor = Color.Red;
}
else if (bp.Length == 17)
{
lbl_bp.BackColor = Color.LightGray;
}
}
else if (inStr.Length == 32 || inStr.Length == 25 || inStr.Length == 34 || inStr.Length == 33 || inStr.Length == 26 || inStr.Length == 31)
{
int indexOfSpace = inStr.IndexOf(':');
string Acc = inStr.Substring(indexOfSpace + 1);
txtData7.Text = Acc;
string test = inStr;
if (test.Length == 25 || test.Length == 34 || test.Length == 33 || test.Length == 26)
{
label21.Text = "Check on patient!";
label21.BackColor = Color.Red;
}
else if (test.Length == 32)
{
label21.Text = "";
label21.BackColor = Color.LightGray;
}
}
else
{
}
if (txtData1.Text != "" && txtData2.Text != "" && txtData3.Text != "" && txtData4.Text != "" && txtData5.Text != "" && txtData6.Text != "" && txtData7.Text != "")
{
try
{
connection2.Open();
OleDbCommand command2 = new OleDbCommand();
command2.Connection = connection2;
command2.CommandText = "insert into MedicalRecord (PatientNumber,FirstName,LastName,IC,Temperature,ECG,Systolic,Diastolic,Pulse) values('" + txt_pnorec.Text + "','" + txt_fnamerec.Text + "','" + txt_lnamerec.Text + "','" + txt_icrec.Text + "','" + txtData2.Text + "','" + txtData3.Text + "','" + txtData4.Text + "','" + txtData5.Text + "','" + txtData6.Text + "')";
command2.ExecuteNonQuery();
MessageBox.Show("Info Stored");
connection2.Close();
txtData1.Text = "";
txtData2.Text = "";
txtData3.Text = "";
txtData4.Text = "";
txtData5.Text = "";
txtData6.Text = "";
txtData7.Text = "";
Thread.Sleep(interval);
MessageBox.Show("Start");
}
catch (Exception ex)
{
MessageBox.Show("Error: " + ex);
}
txtData1.Text = "";
txtData2.Text = "";
txtData3.Text = "";
txtData4.Text = "";
txtData5.Text = "";
txtData6.Text = "";
txtData7.Text = "";
}
}
Thanks in advance.
There are multiple ways to achieve this. One example is to use a task with a delay:
Task.Delay(10000).ContinueWith(x =>
{
//Place the code you want delayed here.
});
Another example could be to use a BackgroundWorker which is made for this exact purpose.
you can use Async and Await
here is a good tutorial in combination with an GUI:
https://www.youtube.com/watch?v=MCW_eJA2FeY
you need to declare your function as async
public async void Foo()
{
...
}
than you can use:
await Task.Delay(10000);
it will release you GUI for the whole Delay and you can use your GUI while the Delay is waiting.
Task.Delay(10000).ContinueWith(x =>
{
//...
});
Have a look at Task.Delay and ContinueWith.
You can use Windows.Forms.Timer to execute something after delay... (with no UI thread freezing). Split your code on two parts. 1. Before delay 2. After delay
public partial class form1 : Form
{
// i used namespace to ensure that we use 'correct' Timer and we do not
// confuse it with System.Timers.Timer or System.Threading.Timer
System.Windows.Forms.Timer tmrDelay;
void SomeMethodWithDelay()
{
// code before delay here
tmrDelay.Enabled = true;
tmrDelay.Tick += Timer_Tick;
}
private void Timer_Tick(object sender, EventArgs e)
{
Thread.Sleep(5000);
// your code here
// disables timer to stop it
tmrDelay.Enabled = false;
}
}
Benefit from using Timer is that it is a native windows forms tool that was specially designed to help with this kind of problems.
However you can still use modern things like Tasks, for example : Task.Factory.StartNew(() => { Thread.Sleep(5000); // your method logic here });
I've created a form that allows for seat booking it has two dropdown menus and a label that changes showing them what seats they have booked. the label resets when I press the reset button but the drop down menus don't, they stay on the selected seats e.g. one menu saying "A" and the other saying "4" I need these to reset to blank can anyone help?
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 courseworkTask3
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
if (comboBox1.SelectedIndex <= 0)
{
button1.Enabled = false;
}
else
{
button1.Enabled = true;
}
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
string temp = comboBox1.Text;
int dropBox1enter;
if (int.TryParse(temp, out dropBox1enter))
{
}
int i = 0;
int seatsFound = 0;
int maxFoundSeats = 0;
int maxFoundSeatsStart = 0;
int maxFoundSeatsEnd = 0;
bool[] rowA = new bool[10];
rowA[0] = true;
rowA[1] = true;
rowA[2] = false;
rowA[3] = false;
rowA[4] = false;
rowA[5] = true;
rowA[6] = true;
rowA[7] = false;
rowA[8] = false;
rowA[9] = false;
bool[] rowB = new bool[10];
rowB[0] = true;
rowB[1] = false;
rowB[2] = false;
rowB[3] = false;
rowB[4] = false;
rowB[5] = true;
rowB[6] = true;
rowB[7] = false;
rowB[8] = false;
rowB[9] = false;
bool[] rowC = new bool[10];
rowC[0] = true;
rowC[1] = false;
rowC[2] = false;
rowC[3] = false;
rowC[4] = false;
rowC[5] = true;
rowC[6] = true;
rowC[7] = false;
rowC[8] = false;
rowC[9] = false;
bool[] rowD = new bool[10];
rowD[0] = true;
rowD[1] = false;
rowD[2] = false;
rowD[3] = false;
rowD[4] = false;
rowD[5] = true;
rowD[6] = true;
rowD[7] = false;
rowD[8] = false;
rowD[9] = false;
bool[] rowE = new bool[10];
rowE[0] = true;
rowE[1] = false;
rowE[2] = false;
rowE[3] = false;
rowE[4] = false;
rowE[5] = true;
rowE[6] = true;
rowE[7] = false;
rowE[8] = false;
rowE[9] = false;
if (comboBox2.Text == "A")
{
while (i < 10 && maxFoundSeats < dropBox1enter)
{
if (rowA[i] == false)
{
seatsFound++;
if (seatsFound > maxFoundSeats)
{
maxFoundSeats = seatsFound;
maxFoundSeatsStart = 1 + i - seatsFound;
maxFoundSeatsEnd = i;
}
}
else
{
seatsFound = 0;
}
i++;
} if (maxFoundSeats == dropBox1enter)
{
label4.Text = "Booked for " + maxFoundSeats + " seat(s) in row A starting, seat " + maxFoundSeatsStart + " to seat " + maxFoundSeatsEnd + ".";
}
else
{
label4.Text = "The seats you have selected are unavailable. #The maximum available is " + maxFoundSeats + " in row A From " + maxFoundSeatsStart + " to " + maxFoundSeatsEnd + ".";
label4.Text = label4.Text.Replace("#", System.Environment.NewLine);
}
}
else
{
if (comboBox2.Text == "B")
{
while (i < 10 && maxFoundSeats < dropBox1enter)
{
if (rowB[i] == false)
{
seatsFound++;
if (seatsFound > maxFoundSeats)
{
maxFoundSeats = seatsFound;
maxFoundSeatsStart = 1 + i - seatsFound;
maxFoundSeatsEnd = i;
}
}
else
{
seatsFound = 0;
}
i++;
}
if (maxFoundSeats == dropBox1enter)
{
label4.Text = "Booked for " + maxFoundSeats + " seat(s) in row B starting, seat " + maxFoundSeatsStart + " to seat " + maxFoundSeatsEnd + ".";
}
else
{
label4.Text = "The seats you have selected are unavailable. #The maximum available is " + maxFoundSeats + " in row B From " + maxFoundSeatsStart + " to " + maxFoundSeatsEnd + ".";
label4.Text = label4.Text.Replace("#", System.Environment.NewLine);
}
}
else
{
if (comboBox2.Text == "C")
{
while (i < 10 && maxFoundSeats < dropBox1enter)
{
if (rowC[i] == false)
{
seatsFound++;
if (seatsFound > maxFoundSeats)
{
maxFoundSeats = seatsFound;
maxFoundSeatsStart = 1 + i - seatsFound;
maxFoundSeatsEnd = i;
}
}
else
{
seatsFound = 0;
}
i++;
}
if (maxFoundSeats == dropBox1enter)
{
label4.Text = "Booked for " + maxFoundSeats + " seat(s) in row C starting, seat " + maxFoundSeatsStart + " to seat " + maxFoundSeatsEnd + ".";
}
else
{
label4.Text = "The seats you have selected are unavailable. #The maximum available is " + maxFoundSeats + " in row C From " + maxFoundSeatsStart + " to " + maxFoundSeatsEnd + ".";
label4.Text = label4.Text.Replace("#", System.Environment.NewLine);
}
}
else
{
if (comboBox2.Text == "D")
{
while (i < 10 && maxFoundSeats < dropBox1enter)
{
if (rowD[i] == false)
{
seatsFound++;
if (seatsFound > maxFoundSeats)
{
maxFoundSeats = seatsFound;
maxFoundSeatsStart = 1 + i - seatsFound;
maxFoundSeatsEnd = i;
}
}
else
{
seatsFound = 0;
}
i++;
}
if (maxFoundSeats == dropBox1enter)
{
label4.Text = "Booked for " + maxFoundSeats + " seat(s) in row D starting, seat " + maxFoundSeatsStart + " to seat " + maxFoundSeatsEnd + ".";
}
else
{
label4.Text = "The seats you have selected are unavailable. #The maximum available is " + maxFoundSeats + " in row D From " + maxFoundSeatsStart + " to " + maxFoundSeatsEnd + ".";
label4.Text = label4.Text.Replace("#", System.Environment.NewLine);
}
}
else
{
if (comboBox2.Text == "E")
{
while (i < 10 && maxFoundSeats < dropBox1enter)
{
if (rowE[i] == false)
{
seatsFound++;
if (seatsFound > maxFoundSeats)
{
maxFoundSeats = seatsFound;
maxFoundSeatsStart = 1 + i - seatsFound;
maxFoundSeatsEnd = i;
}
}
else
{
seatsFound = 0;
}
i++;
}
if (maxFoundSeats == dropBox1enter)
{
label4.Text = "Booked for " + maxFoundSeats + " seat(s) in row E starting, seat " + maxFoundSeatsStart + " to seat " + maxFoundSeatsEnd + ".";
}
else
{
label4.Text = "The seats you have selected are unavailable. #The maximum available is " + maxFoundSeats + " in row E From " + maxFoundSeatsStart + " to " + maxFoundSeatsEnd + ".";
label4.Text = label4.Text.Replace("#", System.Environment.NewLine);
}
}
} //end E
} //end D
} //end C
}
}
private void dropBox1_SelectedIndexChanged(object sender, EventArgs e)
{
}
private void dropBox2_SelectedIndexChanged(object sender, EventArgs e)
{
if (comboBox1.Text != null && comboBox2.Text != null)
{
button1.Enabled = true;
}
}
private void button2_Click(object sender, EventArgs e)
{
label4.Text = "";
}
}
}
As #Rohit Prakash pointed out in the comments to your question, setting the SelectedIndex of a ComboBox to -1 will reset any selections to the Combobox:
(I'm assuming "button2" is your Reset button, you should really name your controls more appropriately)
private void button2_Click(object sender, EventArgs e)
{
label4.Text = "";
comboBox1.SelectedIndex = -1;
comboBox2.SelectedIndex = -1;
}
i have code to format telephone number automatically,
format is 12 3456-7890
1234567890 = 12 3456-7890 (TextLength = 12)
I want if TextLength = 13 format this way
12345678901 = 12 34567-8901 (TextLength = 12) or in another words, change postion of "-" to 1 position right and add last number on last character
my actual code
private void txtFonecom_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Back)
{
}
else
{
if (txtFonecom.TextLength == 2)
{
txtFonecom.Text = txtFonecom.Text + " ";
txtFonecom.SelectionStart = 3;
txtFonecom.SelectionLength = 0;
}
if (txtFonecom.TextLength == 7)
{
txtFonecom.Text = txtFonecom.Text + "-";
txtFonecom.SelectionStart = 8;
txtFonecom.SelectionLength = 0;
}
if (txtFonecom.TextLength == 13)
{
//here i have to change format from 12 3456-7890 to 12 34567-8901
}
}
}
Instead of manually handling the keypresses I would suggest using the MaskedTextBox control with the mask 00 0000-0000 since the control can automatically format the input for you.
Assuming you still prefer to go for a TextBox solution here is the solution:
private void txtFonecom_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Back)
{
}
else
{
if (txtFonecom.TextLength == 2)
{
txtFonecom.Text = txtFonecom.Text + " ";
txtFonecom.SelectionStart = 3;
txtFonecom.SelectionLength = 0;
}
if (txtFonecom.TextLength == 7)
{
txtFonecom.Text = txtFonecom.Text + "-";
txtFonecom.SelectionStart = 8;
txtFonecom.SelectionLength = 0;
}
if (txtFonecom.TextLength == 12)
{
int caretPos = txtFonecom.SelectionStart;
txtFonecom.Text = txtFonecom.Text.Replace("-", string.Empty).Insert(8, "-");
txtFonecom.SelectionStart = caretPos;
}
}
}
Keep in mind you will need to handle the format when the user deletes numbers.
This code will keep the " " and "-" at their places whether user remove or add numbers at any where:
void txtFonecom_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar != (char)Keys.Back)
{
if (txtFonecom.TextLength == 2)
{
txtFonecom.Text = txtFonecom.Text + " ";
txtFonecom.SelectionStart = 3;
}
if (txtFonecom.TextLength >= 7 && txtFonecom.TextLength < 12)
{
if (txtFonecom.Text.Substring(2, 1) == " ") //check if " " exists
{ }
else //if doesn't exist, then add " " at index 2 (character no. 3)
{
txtFonecom.Text = txtFonecom.Text.Replace(" ", String.Empty);
txtFonecom.Text = txtFonecom.Text.Insert(2, " ");
}
txtFonecom.Text = txtFonecom.Text.Replace("-", String.Empty); //now add "-" at index 7 (character no. 8)
txtFonecom.Text = txtFonecom.Text.Insert(7, "-");
txtFonecom.SelectionStart = txtFonecom.Text.Length;
}
if (txtFonecom.TextLength >= 12)
{
if (txtFonecom.Text.Substring(2, 1) == " ") //check if " " exists
{ }
else //if doesn't exist, then add " " at index 2 (character no. 3)
{
txtFonecom.Text = txtFonecom.Text.Replace(" ", String.Empty);
txtFonecom.Text = txtFonecom.Text.Insert(2, " ");
}
txtFonecom.Text = txtFonecom.Text.Replace("-", String.Empty); //now add "-" at index 8 (character no. 9)
txtFonecom.Text = txtFonecom.Text.Insert(8, "-");
txtFonecom.SelectionStart = txtFonecom.Text.Length;
}
}
}
Or if you only want numbers in textbox, then use
if ((int)e.KeyChar >= 48 && (int)e.KeyChar <= 57)