在 C# 程序中使用 sql server insert 语句答案

【问题标题】：using sql server insert statement in C# programe在 C# 程序中使用 sql server insert 语句
【发布时间】：2014-03-30 13:37:53
【问题描述】：

大家好，我正在尝试将从前端获得的值插入到 sql server 数据库中。这是我的代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Geocoding.Google;
using Geocoding;
using System.Data.SqlClient;
public partial class regforswa : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        string lat;
        string longi;
        IGeocoder geocoder = new GoogleGeocoder() { };
        Address[] addresses = 
        geocoder.Geocode(TextBox4.Text+TextBox5.Text+TextBox6.Text).ToArray();
        foreach (Address adrs in addresses)
        {
           //Response.Write("lat=" +adrs.Coordinates.Latitude.ToString());
            //Response.Write( "longi="+ adrs.Coordinates.Longitude.ToString());
        }
        SqlConnection conn = new SqlConnection("Data Source=ADMIN-PC\\SQLEXPRESS;Initial Catalog=swa1;User Id=swa1;Password=swa1;");//datasource=localhost name,initial catalog=db name
        //integrated security=windiws authentication OR for sql authentication specify
        //userid and password 
        conn.Open();//opens connection with the database
        try
        {//exeption handling

            String uname=TextBox1.Text;
            String pwd=TextBox3.Text;
            String mnumber = TextBox7.Text;
            String sques = DropDownList1.Text;
            String res = TextBox8.Text;
            String adress = TextBox4.Text;
            String cty = TextBox5.Text;
            String zpcode = TextBox6.Text;
           // Response.Write("uname"+uname +"pwd"+ pwd);
            SqlCommand newcomm = new SqlCommand("INSERT INTO regforswa(username,password,mno,sq,response,address,city,zipcode) VALUES (uname,pwd,mnumber,sques,res,adress,cty,zpcode)", conn);
            if (newcomm.ExecuteNonQuery() == 1)
            {            
                result.Visible = true;
                result.Text = "entered successfully";
            }
            else
            {
                result.Text = "not entered";
            }
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }
        finally
        {
            conn.Close();
        }
    }

}

但我收到此错误

列名“uname”无效。列名“pwd”无效。列无效名称'mnumber'。列名“sques”无效。列名无效 'res'。列名“地址”无效。列名“cty”无效。列名“zpcode”无效。

我检查了我的数据库列名，它是完美的。请有人帮忙。为什么我会收到这个错误？

【问题讨论】：

标签： c# sql-server visual-studio-2010

【解决方案1】：

在 INSERT 命令中，您不能以这种方式直接传递变量值。您使用参数占位符，然后构建命令的参数集合

    string uname=TextBox1.Text;
    string pwd=TextBox3.Text;
    string mnumber = TextBox7.Text;
    string sques = DropDownList1.Text;
    string res = TextBox8.Text;
    string adress = TextBox4.Text;
    string cty = TextBox5.Text;
    string zpcode = TextBox6.Text;
    SqlCommand newcomm = new SqlCommand(@"INSERT INTO regforswa
             (username,password,mno,sq,response,address,city,zipcode) VALUES  
             (@uname,@pwd,@mnumber,@sques,@res,@adress,@cty,@zpcode)", conn);
     newcomm.Parameters.AddWithValue("@uname", uname);
     ..... and so on for the other parmaters required by the placeholders

     if (newcomm.ExecuteNonQuery() == 1)

另外，请记住，参数的输入应与您的字段要求完全相同。例如，如果字段 mno 是整数类型，那么您需要转换该参数的值

     newcomm.Parameters.AddWithValue("@mnumber", Convert.ToInt32(mnumber));

【讨论】：