输出四位自然数中各位数字之和为6并且各位数字互不相同的数，并统计个数。C# 求代码 谢谢

输出四位自然数中各位数字之和为6并且各位数字互不相同的数，并统计个数。C# 求代码 谢谢

private void button1_Click(object sender, EventArgs e)
{
int i,qw,bw,sw,gw,count=0;
for (i = 1000; i < 10000; i++)
{
qw = i / 1000;
bw = i % 1000 / 100;
sw = i % 100 / 10;
gw = i % 10;
this.textBox2.Text = i.ToString();
if ((qw + bw + sw + gw) != 6)
continue;
if ((qw - bw) * (qw - sw) * (qw - gw) == 0) continue;
if ((bw - sw) * (bw - gw) * (sw - gw) == 0) continue;
if (count > 0) this.textBox1.Text += ",";
this.textBox1.Text += i;
count++;

}
this.textBox2.Text = "共有" + count + "满足条件的数";
}

只可能是0.1.2.3，然后组合就有4*3*2*1=24种