参数没有默认值，请帮帮我. [英] Parameter has no default value please help me.
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问题描述
大家好，请帮帮我
我有以下代码
Hi Guys, Please help me out
I am having the following code
<body>
<form id="form1" runat="server">
<div>
<div>
Have Pan Card:
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" Width="316px" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
<asp:ListItem>-----select----- </asp:ListItem>
<asp:ListItem>yes</asp:ListItem>
<asp:ListItem>no</asp:ListItem>
</asp:DropDownList><br />
</div>
<div id="div1" runat="server">Enter Ist Choice
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> </div>
</div>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
</form>
</body>
后面的代码在这里
and the code behind is here
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.OleDb;
public partial class demo : System.Web.UI.Page
{
string pan, panno;
OleDbConnection con = new OleDbConnection(ConfigurationManager.ConnectionStrings["adbudhconnection"].ConnectionString);
protected void Page_Load(object sender, EventArgs e)
{
div1.Visible = false;
}
protected void Button1_Click(object sender, EventArgs e)
{
con.Open();
OleDbCommand cmd = new OleDbCommand("insert into demo(pan,panno)values(@pan,@panno)", con);
cmd.Parameters.AddWithValue("@pan", pan);
cmd.Parameters.AddWithValue("@panno", panno);
cmd.ExecuteNonQuery();
con.Close();
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
if (DropDownList1.SelectedItem.Text == "yes")
{
div1.Visible = true;
pan = DropDownList1.SelectedItem.Text;
panno = TextBox1.Text;
}
else if (DropDownList1.SelectedItem.Text == "no")
{
pan = DropDownList1.SelectedItem.Text;
panno = "n/a";
}
}
}
这给出了错误，
参数@pan没有默认值
请帮助其紧急
this gives the error that
Parameter @pan has no default value
please help its urgent
推荐答案
如果在列表中选择一个项目之前单击提交"按钮，则pan将为空.在Button1_Click中获取pan的值.
If you click the submit button before selecting an item in the listpanwill be empty. Get the value ofpaninsideButton1_Click.
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