过滤要添加到 stringbuilder 的数据网格元素

Question

我的应用程序有一个导出按钮，它打开一个保存文件对话框和一个下拉框，允许用户选择客户端和将文件保存到的路径，单击导出按钮后，我想从数据中获取数据网格，其中客户端名称与下拉列表中找到的匹配并将这些发送到文件，目前我的代码如下但是它只返回列的标题，有人知道解决方案吗？ ：

      foreach (DataRow dr in this.CalcDataSet.MInve)
        {

            bool hasValue = false;

            for (int i = 0; i < dr.ItemArray.Count(); i++)
            {
                //if doesnt match selected client
                if    (!dr[i].ToString().Contains(dropboxClientList.SelectedValue.ToString()))
                hasValue = true;
            }

            //else 
            if (!hasValue) rowsToADD.Add(dr);

            foreach (DataRow field in rowsToADD)
            {   
              str.Append(field.ToString() + ",");
            }
            str.Replace(",", "\n", str.Length - 1, 1);
        }


        try
        {
            System.IO.File.WriteAllText(Filepath, str.ToString());
        }
        catch (Exception ex)
        {
            MessageBox.Show("Write Error :" + ex.Message);
        }

Answer 1

取自this SO post

string file_name = "C:\\test1.txt";

System.IO.StreamWriter objWriter;

objWriter = new System.IO.StreamWriter(file_name);

int count = dgv.Rows.Count;

for (int row = 0; row < count; row++)
{
    int colCount = dgv.Rows[row].Cells.Count;

    // EDIT inserted if statement
    string selectedValue = dropboxClientList.SelectedValue.ToString();
    string clientName = dgv.Rows[row].Cells[1].Value.ToString();

    // If the current row contains the selected client name 
    if (clientName.Contains(selectedValue)
    {
        // Write the columns for the current row
        for ( int col = 0; col < colCount; col++)  
        {            
            objWriter.WriteLine(dgv.Rows[row].Cells[col].Value.ToString());
        }
    }

    // record seperator could be written here.
}

objWriter.Close();