Question

我有这段代码可以通过文本框从用户那里接收一个数字，然后使用该值和SQL表中的两个值进行简单的计算。我进行了调试，未收到任何错误，但gridview中的标签没有填充。任何帮助将不胜感激。

protected void Calculate_Click(object sender, EventArgs e)
{
    SqlConnection conn = new SqlConnection(WebConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
    SqlCommand cmd = new SqlCommand("SELECT [Divide], [Calc] FROM [Parrts] WHERE (([Region] = 'East Coast') AND ([Model] = @Model) AND ([SashSize] = @SashSize) AND ([Operation] = @Operation) AND ([PartDesc] = @PartDesc) AND ([Description] = @Description) AND ([Lites] =@Lites))", conn);

    SqlParameter Model = new SqlParameter("@Model", ddModel.SelectedValue);
    cmd.Parameters.Add(Model);
    SqlParameter SashSize = new SqlParameter("@SashSize", ddSashSize.SelectedValue);
    cmd.Parameters.Add(SashSize);
    SqlParameter Operation = new SqlParameter("@Operation", ddOperation.SelectedValue);
    cmd.Parameters.Add(Operation);
    SqlParameter Part = new SqlParameter("@PartDesc", ddPart.SelectedValue);
    cmd.Parameters.Add(Part);
    SqlParameter Color = new SqlParameter("@Description",ddColor.SelectedValue);
    cmd.Parameters.Add(Color);
    SqlParameter Lites = new SqlParameter("@Lites",ddLites.SelectedValue);
    cmd.Parameters.Add(Lites);

    conn.Open();
    cmd.Connection = conn;

    SqlDataReader rdr = cmd.ExecuteReader();
    while (rdr.Read())
    {
        Int32 Divide = (int)rdr["Divide"];
        double Calc = (double)rdr["Calc"];

        int HW = Convert.ToInt32(length_txt.Text);
        foreach (GridViewRow row in GridViewAMI.Rows)
        {
            string Length = ((Label)row.FindControl("Length")).Text;
            Response.Write(Length);
            Length = ((HW / Divide) - Calc).ToString();
        }
    }
    rdr.Close();
    cmd.Dispose();
    conn.Close();
}

Answer 1

由于我看不到您再次填充标签，因此可能会有所帮助：

foreach (GridViewRow row in GridViewAMI.Rows)
{
    // Get the Label safely so you can manipulate it later
    Label rowLabel = row.FindControl("Length") as Label;

    // If you - for whatever reason - can't get the Label, skip this row
    if(rowlabel == null)
        continue;

    string length = rowLabel.Text;
    Response.Write(length);
    length = ((HW / Divide) - Calc).ToString();

    // Populate the Label with the new Data
    rowLabel.Text = length;
}

Answer 2

尝试一下：

foreach (GridViewRow row in GridViewAMI.Rows)
{
    Label lbl = (Label)row.FindControl("Length");
    string length = lbl.Text;
    Response.Write(length);
    length = ((HW / Divide) - Calc).ToString();
    lbl.Text = length;
}

您忘了将文本放回Label。

标签不填充

2 个答案: