C# 如何在asp.net网站中将数据插入sql server？

我尝试从vs 2008中的网站构建中将数据插入sql server。为此，我使用了按钮单击事件。我尝试了youtube中显示的代码，但代码不起作用。它在我的网站中显示错误

.aspx.cs文件中的代码是

public partial class _Default : System.Web.UI.Page 
{
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);

protected void Page_Load(object sender, EventArgs e)
{
    conn.Open();
}
protected void btnInsert_Click(object sender, EventArgs e)
{
    SqlCommand cmd = new SqlCommand("insert into Insert    values('"+txtCity.Text+"','"+txtFName.Text+"','"+txtLName.Text+"')",conn);
    cmd.ExecuteNonQuery();
    conn.Close();
    Label1.Visible =true;
    Label1.Text = "Your data inserted successfully";
    txtCity.Text = "";
    txtFName.Text = "";
    txtLName.Text = "";
}

}

---

`

好的，让我们稍微修改一下代码。你正在到达那里：

var cnnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
var cmd = "insert into Insert values(@City,@FName,@LName)";
using (SqlConnection cnn = new SqlConnection(cnnString))
{
    using (SqlCommand cmd = new SqlCommand(cmd, cnn))
    {
        cmd.Parameters.AddWithValue("@City",txtCity.Text);
        cmd.Parameters.AddWithValue("@FName",txtFName.Text);
        cmd.Parameters.AddWithValue("@LName",txtLName.Text);

        cnn.Open();
        cmd.ExecuteNonQuery();
    }
}

关于修改后的代码，有几点需要注意

• 它利用

  using

  语句来确保资源得到适当的处置
• 它被参数化，以确保不可能进行SQL注入
• 它不会将连接对象存储在任何地方，请清除已存储的连接

SQL

Create procedure insert
(@City,@FirstName,@LastName)
{
insert into tablename (City,FName,LName)
values(@City,@FirstName,@LastName)
}

C#

**

---

**

您收到的错误是什么？我收到的错误是我收到的错误是NullReferenceException未经用户代码处理…对象引用未设置为objectPlus的实例：您不需要调用

cnn.Open（）。在定义参数时无需打开连接…@marc_s，这是一个极好的观察结果！我相信我会改变我的标准（你在上面看到：D）就是这样。谢谢！你能给你的代码添加一些解释吗？这段代码实际上不会执行命令-它只是在生成命令后打开和关闭一个连接。您至少需要一个cmd.ExecuteNonQuery（）或其他命令。
Create procedure insert
(@City,@FirstName,@LastName)
{
insert into tablename (City,FName,LName)
values(@City,@FirstName,@LastName)
}

SqlConnection con=new sqlconnection("give ur connection string here");
sqlcommand cmd=new sqlcommand();
con.open();
cmd=new sqlcommand("insert",con);
cmd.commandtype=commandtype.storedprocedure;
cmd.parameters.addwithvalue("@City",txtCity.text);
cmd.parameters.addwithvalue("@FName",txtFName.text);
cmd.parameters.addwithvalue("@LNAme",txtLName.text);
cmd.ExecuteNonQuery();
con.close();

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
public partial class _Default : System.Web.UI.Page
{
    SqlConnection con = new SqlConnection("Data Source=.\\SQLEXPRESS;Initial Catalog=mrinmoynandy;User ID=**;Password=****");
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    protected void SumbitBtn_Click(object sender, EventArgs e)
    {
        SqlCommand cmd = new SqlCommand("insert into streg(Name,Father,Mother,Dob,Sex,Category,Maritial,Vill,Po,Ps,Dist,State,Pin,Country) values (@name,@father,@mother,@dob,@sex,@category,@maritial,@vill,@po,@ps,@dist,@state,@pin,@country)", con);
        cmd.Parameters.AddWithValue(@"name", StNumTxt.Text);
        cmd.Parameters.AddWithValue(@"father", FatNumTxt.Text);
        cmd.Parameters.AddWithValue(@"mother", MotNumTxt.Text);
        cmd.Parameters.AddWithValue(@"dob", DobRdp.SelectedDate);
        cmd.Parameters.AddWithValue(@"sex", SexDdl.SelectedItem.Text);
        cmd.Parameters.AddWithValue(@"category", CategoryDdl.SelectedItem.Text);
        cmd.Parameters.AddWithValue(@"maritial", MaritialRbl.SelectedItem.Text);
        cmd.Parameters.AddWithValue(@"vill", VillTxt.Text);
        cmd.Parameters.AddWithValue(@"po", PoTxt.Text);
        cmd.Parameters.AddWithValue(@"ps", PsTxt.Text);
        cmd.Parameters.AddWithValue(@"dist", DistDdl.SelectedItem.Text);
        cmd.Parameters.AddWithValue(@"state", StateTxt.Text);
        cmd.Parameters.AddWithValue(@"pin", PinTxt.Text);
        cmd.Parameters.AddWithValue(@"country", CountryTxt.Text);
        con.Open();        
        con.Close();        
    }
}
Thanks
Mrinmoy Nandy
Phone No.: +91 9800451398