c# - c#如何在回发后保持我的单选按钮选择

Question

这就是我的 gridview 的样子：

基本上，我选择“你”作为正确答案。

但是在我点击“+”按钮后，单选按钮的选择被删除了。

如何为每一行 gridview 保留我对单选按钮的选择？

这是我的代码：

 protected void Page_Load(object sender, EventArgs e)
 {

     if (!Page.IsPostBack)
     {
         SetInitialRow();
         dropActivity(); // ignore this , this is for drop down list
         dropTask();  // ignore this , this is for drop down list

     }
 }

private void SetInitialRow()
{
    DataTable dt = new DataTable();
    DataRow dr = null;
    dt.Columns.Add(new DataColumn("Question", typeof(string)));
    dt.Columns.Add(new DataColumn("Hints No.1", typeof(string)));
    dt.Columns.Add(new DataColumn("Hints No.2", typeof(string)));

    dr = dt.NewRow();
    dr["Question"] = string.Empty;
    dr["Hints No.1"] = string.Empty;
    dr["Hints No.2"] = string.Empty;

    dt.Rows.Add(dr);

    //Store the DataTable in ViewState
    ViewState["CurrentTable"] = dt;

    GridView1.DataSource = dt;
    GridView1.DataBind();
}

private void AddNewRowToGrid()
{
    int rowIndex = 0;

    if (ViewState["CurrentTable"] != null)
    {
        DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
        DataRow drCurrentRow = null;
        if (dtCurrentTable.Rows.Count > 0)
        {
            for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
            {
                //extract the TextBox values
                TextBox box1 = (TextBox)GridView1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
                TextBox box2 = (TextBox)GridView1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
                TextBox box3 = (TextBox)GridView1.Rows[rowIndex].Cells[3].FindControl("TextBox3");

                drCurrentRow = dtCurrentTable.NewRow();

                dtCurrentTable.Rows[i - 1]["Question"] = box1.Text;
                dtCurrentTable.Rows[i - 1]["Hints No.1"] = box2.Text;
                dtCurrentTable.Rows[i - 1]["Hints No.2"] = box3.Text;

                rowIndex++;
            }
            dtCurrentTable.Rows.Add(drCurrentRow);
            ViewState["CurrentTable"] = dtCurrentTable;

            GridView1.DataSource = dtCurrentTable;
            GridView1.DataBind();
        }
    }
    else
    {
        Response.Write("ViewState is null");
    }

    //  Set Previous Data on Postbacks
    SetPreviousData();
}

private void SetPreviousData()
{
    int rowIndex = 0;
    if (ViewState["CurrentTable"] != null)
    {
        DataTable dt = (DataTable)ViewState["CurrentTable"];
        if (dt.Rows.Count > 0)
        {
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                TextBox box1 = (TextBox)GridView1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
                TextBox box2 = (TextBox)GridView1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
                TextBox box3 = (TextBox)GridView1.Rows[rowIndex].Cells[3].FindControl("TextBox3");

                RadioButton radiobtn1 = (RadioButton)GridView1.Rows[i].Cells[2].FindControl("RadioButton1");
                RadioButton radiobtn2 = (RadioButton)GridView1.Rows[i].Cells[3].FindControl("RadioButton2");

                //Setting previous text to the respective textboxes based on columns.
                box1.Text = dt.Rows[i]["Question"].ToString();
                box2.Text = dt.Rows[i]["Hints No.1"].ToString();
                box3.Text = dt.Rows[i]["Hints No.2"].ToString();

                if (radiobtn1.Checked == true)
                {
                    ViewState["RadioButtonStatus"] = radiobtn1.Checked;
                }

                if (radiobtn2.Checked == true)
                {
                    ViewState["RadioButtonStatus"] = radiobtn2.Checked;
                }

                Session["Question1"] = box1.Text;
                rowIndex++;
            }
        }
    }
}

基本上我需要为我创建的每一行保留单选按钮的选择。

Answer 1

考虑更改“+”按钮以在客户端触发事件，而不是发布到服务器以获取新行。然后，当您将集合发布到服务器上的“保存”事件处理程序时，您可以循环访问该集合。

目前似乎正在发生的是您点击“+”按钮的回发。回发会导致这些单选按钮被清除。我看到您正在尝试通过 ViewState 保留状态，但您正在为同一 ViewState 属性保存已检查的状态。

请参阅下面代码中的差异。

    if (radiobtn1.Checked == true)
    {
        ViewState["RadioButtonStatus"] = radiobtn1.Checked;
    }

    if (radiobtn2.Checked == true)
    {
        ViewState["DifferentRadioButtonStatus"] = radiobtn2.Checked;
    }

以下是您的 AddNewRow 方法的一些更新。这里发生了很多事情，这可能有点过度设计。希望它可以帮助您朝着正确的方向前进。

private void AddNewRowToGrid()
{
    int rowIndex = 0;

    if (ViewState["CurrentTable"] != null)
    {
        DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];

            var drCurrentRow = dtCurrentTable.NewRow();
            dtCurrentTable.Rows.Add(drCurrentRow);

        // Updated from > 0 to > 1 since the first action you're taking is in GridView1.Rows[1] via the for loop below
        if (dtCurrentTable.Rows.Count > 1)
        {
            for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
            {
                //extract the TextBox values
                TextBox box1 = (TextBox)GridView1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
                TextBox box2 = (TextBox)GridView1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
                TextBox box3 = (TextBox)GridView1.Rows[rowIndex].Cells[3].FindControl("TextBox3");
                dtCurrentTable.Rows[i - 1]["Question"] = box1.Text;
                dtCurrentTable.Rows[i - 1]["Hints No.1"] = box2.Text;
                dtCurrentTable.Rows[i - 1]["Hints No.2"] = box3.Text;

                rowIndex++;
            }


            ViewState["CurrentTable"] = dtCurrentTable;

            GridView1.DataSource = dtCurrentTable;
            GridView1.DataBind();
        }
    }
    else
    {
        Response.Write("ViewState is null");
    }

    //  Set Previous Data on Postbacks
    SetPreviousData();
}