(回帖给分)在将 varchar 值 转换成数据类型 int 时失败。
在将 varchar 值 'System.Web.UI.HtmlControls.HtmlInputText' 转换成数据类型 int 时失败。

我用datalist写了一个添加的代码

数据表里有字段



在一个表格中添加产品的代码是


  protected void btnNew_Click(object sender, ImageClickEventArgs e)
  {
  DBconn DB = new DBconn();
  string strSql = "insert into book (bookname,typeid,write,chubanshename,bookprice,xiancunnumber) values('" + txtBookName.Value + "','" + ddlType.Text + "','" + txtWrite + "','" + txtChuban.Value + "','" + txtBookPrice + "'," +txtBookCount.Value + ")";
  DB.ExecuteNonQuery(strSql);
  btnNew.Visible = false;
  Panel1.Visible = false;
  DataList1.Visible = true;
  DataBindDataList();
  initTable();

  }


DBconn.cs文件 用于连接。。倒数第二句话 cmd.ExecuteNonQuery(); 报错 说 在将 varchar 值 'System.Web.UI.HtmlControls.HtmlInputText' 转换成数据类型 int 时失败。



public class DBconn
{
private string strConn;
  private SqlConnection con;
  private SqlCommand cmd;
  private SqlDataAdapter sda;
  private DataSet ds;
   



public DBconn()
{
  strConn = CreateConnn();
  con = new SqlConnection(strConn);
  cmd = new SqlCommand();
  sda = new SqlDataAdapter();
  ds = new DataSet();


  }

  public string CreateConnn() {
  return ConfigurationManager.ConnectionStrings["libraryConnectionString"].ConnectionString;
  }
  public DataSet Getds(string StrSql) {
  con.Open();
  sda = new SqlDataAdapter(StrSql, con);
  sda.Fill(ds);
  con.Close();
  return ds;
  }

  public void ExecuteNonQuery(string strSql) {
  con.Open();
  cmd.CommandText = strSql;
  cmd.Connection = con;
  cmd.ExecuteNonQuery();
  con.Close();

  }

}






------解决方案--------------------
string strSql = "insert into book (bookname,typeid,write,chubanshename,bookprice,xiancunnumber) values('" + txtBookName.Value + "','" + ddlType.Text + "','" + txtWrite + "','" + txtChuban.Value + "','" + txtBookPrice + "'," +txtBookCount.Value + ")";
红的部分对应你数据库字段都是整型，也要进行类型转换

改成这样试试(先判断这些值ddlType.Text不为空)

string strSql = "insert into book (bookname,typeid,write,chubanshename,bookprice,xiancunnumber) values('" + txtBookName.Value + "','" + Convert.ToInt32(ddlType.SelectedValue.Trim()) + "','" + txtWrite + "','" + txtChuban.Value + "','" + Convert.ToInt32(txtBookPrice.Value.Trim()) + "'," +Convert.ToInt32(txtBookCount.Value.Trim()) + ")";
------解决方案--------------------
1楼正解。从页面读到的数字是string类型的，要强制转换一下，用int.Parse()也可以
------解决方案--------------------
string类型转换成int类型 使用int.Parse()
------解决方案--------------------
你的bookprice把不是int类型吗？
------解决方案--------------------
int.tryparse一下
------解决方案--------------------

探讨

string strSql = "insert into book (bookname,typeid,write,chubanshename,bookprice,xiancunnumber) values('" + txtBookName.Value + "','" + ddlType.Text + "','" +