在c#中增加1

Question

我正在尝试计算ID为3的DataList中的行,并将值放在标签中.

for (int i = 0; i < Product.Items.Count; ++i)
{    
    if (table.Rows[i]["id"].ToString() == "3")
    {
        int x = x + 1;
        lblCounter.text = x.ToString
    }
}

Answer 1

lblCounter.Text = table.Rows.OfType<DataRow>().Count(row => row["id"] == 3).ToString();

根据KooKiz的评论编辑,假设表是一个DataTable.

Answer 2

int x = x + 1;

不管用.你必须做类似的事情

int x = 0;

循环之前和

x = x + 1;

在里面.另外,您可能希望在循环之后放置lblCounter.text = x.ToString,因此tu只需更新一次.

这使得

int x = 0;
for (int i = 0; i < Product.Items.Count; ++i)
  if (table.Rows[i]["id"].ToString() == "3")
    x = x + 1;
lblCounter.text = x.ToString();

Answer 3

将declation移动x到外部范围.

int x=0;
for (int i = 0; i < Product.Items.Count; ++i)
 if (table.Rows[i]["id"].ToString() == "3")
 {
      x = x + 1;
      lblCounter.text = x.ToString
 }

改进的一个:

int x = 0;
for (int i = 0; i < Product.Items.Count; ++i)
   if (table.Rows[i]["id"].ToString() == "3")
      x = x + 1;
lblCounter.text = x.ToString

Answer 4

int x = 0;

for (int i = 0; i < Product.Items.Count; ++i)
{
     if (table.Rows[i]["id"].ToString() == "3")
     {
       x++;
     }
}

lblCounter.Text = x.ToString();