C# structure and sorting

I had an exam this morning i couldn't figure it out. it looks like doesn't matter now because the exam was this
morning but i still want to know how to do it....

i have 2 button: Add(btn_ADD) and Sort(btn_SORT)
1 textbox ( textbox1 )and 1 listbox (listbox1)

Everything is working except for 1 problem:

The teacher add 3 string: 12345
12
abc
(my code is sorting like this, and this is wrong)
Then click the sort buttin: abc
12345
12
(how to sort like this?)
the correct sorting would be: abc
12
12345

struct SString
{
public string m_Sname;

public SString(string s)
{
m_Sname = s;
}
public override string ToString()
{
return string.Format(m_Sname.ToString());
}
}
List m_list = new List();
public Form1()
{
InitializeComponent();
}

private void btn_ADD_Click(object sender, EventArgs e)
{
try
{
SString temp = new SString(textBox1.Text);
m_list.Add(temp);
listBox1.Items.Add(temp.ToString());
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}

private void btn_SORT_Click(object sender, EventArgs e)
{
SString[] sort;
sort = m_list.ToArray();
BubbleSort_string(sort);
listBox1.Items.Clear();
m_list.Clear();
foreach (SString n in sort)
{
m_list.Add(n);
listBox1.Items.Add(n.ToString());

}
}
private void BubbleSort_string(SString[] ArrayOfString)
{
SString tempS = new SString();
//number of passes through array equals number of elements - 1
for (int iPass = 0; iPass < ArrayOfString.Length - 1; iPass++)
{
//scan through the array looking for swaps
for (int iScan = 0; iScan < ArrayOfString.Length - 1; iScan++)
{
char a = string.Format(ArrayOfString[iScan].m_Sname).ToCharArray()[0];
char b = string.Format(ArrayOfString[iScan + 1].m_Sname).ToCharArray()[0];
int x = (int)a;
int y = (int)b;
if (x < y)
{
tempS = ArrayOfString[iScan];
ArrayOfString[iScan] = ArrayOfString[iScan + 1];
ArrayOfString[iScan + 1] = tempS;
}
}
}
return;
}

3 Replies

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

Vulpes14y ago
To make it ascending, change this line:

if (x < y)

to this:

if (x > y)
Jonathan Crispe14y ago
how can i make it ascending?
Vulpes14y ago
Well, you're doing an descending sort based on the ASCII value of the first character of each string.

Consequently, whether "12345" sorts before "12" or not is indeterminate because both of them start with the same character which has an ASCII value of 49.

However, both of them will always sort after "abc" because 'a' has an ASCII value of 97.

Is this in fact what you were told to do or are you supposed to sort on the whole string, not just the first character?