作者xyybks (xyy)
看板C_Sharp
標題[問題] 物件屬性
時間Thu Jan 6 19:51:21 2011
先奉上程式碼
public partial class Form1 : Form
{
Label[]led = new Label[7];
int a=1;
int count
public Form1()
{
InitializeComponent();
timer1.Enabled = true;
timer1.Interval = 500;
label9.Text = "旋轉: 順時針";
private void button2_Click(object sender, EventArgs e)
{
count = 0;
if (count < 7)
{
led[count + 1].BackColor = Color.Red;
led[count].BackColor = Color.Gray;
count++;
}
else
{
led[0].BackColor = Color.Red;
led[7].BackColor = Color.Gray;
count = 0;
}
timer1.Enabled = true;
}
private void button1_Click(object sender, EventArgs e)
{
if (a==1)
{
label9.Text = "旋轉: 逆時針";
a = 0;
}
else
{
label9.Text = "旋轉: 順時針";
a = 1;
}
}
private void timer1_Tick(object sender, EventArgs e)
{
if (a==1)
{
if (count < 7)
{
led[count + 1].BackColor =Color.Red;
led[count].BackColor = Color.Gray;
count++;
}
else
{
led[0].BackColor = Color.Red;
led[7].BackColor = Color.Gray;
count = 0;
}
}
else
if (count > 0)
{
led[count - 1].BackColor = Color.Red;
led[count].BackColor = Color.Gray;
count--;
}
else
{
led[7].BackColor = Color.Red;
led[0].BackColor = Color.Gray;
count = 7;
}
}
這個程式，按偵錯時，在這一行""led[count + 1].BackColor =Color.Red;""
會出現這個問題""並未將物件參考設定為物件的執行個體""
感覺上是沒有創造出Label這一個物件，所以無法控制BackColor這一個屬性
拜託板上的各路高手了，這個程式已經想好幾天了
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◆ From: 218.35.223.137
1F：→ ken1325:你沒有建物件你要他控制什麼 01/06 20:34
2F：→ ken1325: led[count + 1] = label1; 01/06 20:35
3F：→ ken1325:在出錯的code上面把這行加進去 01/06 20:35
4F：→ ken1325:把你在form上拉好的label物件指派給led[count + 1] 01/06 20:36
5F：→ ken1325:你一開始建了label陣列但你沒有做初始化 01/06 20:39
6F：→ ken1325:for (int i = 0; i < 7; i++) 01/06 20:41
7F：→ ken1325:{ 01/06 20:41
8F：→ ken1325: led[i] = new Label(); 01/06 20:41
9F：→ ken1325:} 01/06 20:41
10F：→ xyybks:感謝ken1325大，解決了問題 01/11 12:01