How to generate sequecnce Number?

selva kumar

Hi I am developing windows application..i have 1 combo box containing Ford,honda,,,list items..and i have two label one for displaying date another one is to generate sequence number(from 01-50)....

if i am selecting ford 5 times with todays date..the sequence number should be generate 01,02,03,04,05....

then i m selecting 5 times With todays date the sequence number should be generate 01,02,03,04,05.....

if i m selecting 5 times on tomorrows date the sequence number should be generate 01,02,03,04,05...same for also.

Can any one tell me a logic.....

8 Replies

Know the answer? Post it — somebody with the same question will find it here.

Chasse Court13y ago
Without programming a stitch of code here might I suggest that you use a sequence in the following format:

YYYYMMDDHHMMSS

By doing this you will end up with as an example.
20130628164301<01>
20130628165531<02>

By doing this it may not actually necessary to have the sequence number on the end of your data as the Date/Time stamp is unique and orderable so you can select a sequence for the make, sub select for the correct date and then order by the time in ascending order to get a perfectly ordered list without a sequence number on the end.
Vulpes13y ago
I can't see how that exception can be thrown from the code I posted.

On what line does it occur?
selva kumar13y ago
i m getting this error...

Object reference not set to an instance of an object.

how to clear..
Vulpes13y ago
The code to do something like that would be along these lines:

private void Form1_Load(object sender, EventArgs e)
{
string[] makes = { "Ford", "Honda" };
comboBox1.DataSource = makes;
countMakes = new int[comboBox1.Items.Count];
comboBox1.SelectedIndex = -1;
today = DateTime.Today;
label1.Text = today.ToLongDateString();
}

private int[] countMakes;
private DateTime today;

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
int index = comboBox1.SelectedIndex;
if (index == -1) return;
if (DateTime.Today > today)
{
Array.Clear(countMakes, 0, countMakes.Length);
today = DateTime.Today;
}
countMakes[index]++;
string text = "";
for (int i = 1; i <= countMakes[index]; i++)
{
text += i.ToString("D2");
if (i < countMakes[index])
{
text += ",";
}
}
label2.Text = text;
}
selva kumar13y ago
sequence number contains 01,02,03...50
Rohit Kapdi13y ago
ur sequence number only contain 01,02,03,04,....,49,50 or is their any specific format for that? if so please mention the format so i can help u in that manner
selva kumar13y ago
no it does't working....i want out put logic from front end....can u tell me another way...
Pankaj Pandey13y ago
hello

I am just giving logic, you have to write code .if helped then mark as answered.

create table with following detail

date item sequence

use given query

select top(1) * from table where date="your data" and item="your item" order by sqquence desc

read it in front end and check..

if(table.rows.count>0)
{
sequence=sequence+1;
}
else
{
sequence=1;
}

and save date,item and sequence into table.