Question

尝试添加到数据库时出现未处理的错误？ OdbcParameterCollection只接受非null的OdbcParameter类型对象，而不接受String对象。

    protected void Button1_Click(object sender, EventArgs e)
    {

    string email = TextBox1.Text; //added variable name
    string firstname = TextBox2.Text;
    string secondname = TextBox3.Text;
    string dob = TextBox4.Text;
    string location = TextBox5.Text;
    string aboutme = TextBox6.Text;

    OdbcConnection cn = new OdbcConnection("Driver={MySQL ODBC 3.51 Driver}; Server=localhost; Database=gymwebsite; User=root; Password=;");
    cn.Open();
    OdbcCommand cmd = new OdbcCommand("INSERT INTO User (Email, FirstName, SecondName, DOB, Location, Aboutme) VALUES (email, firstname, secondname, dob, location, aboutme)"); // fixed incomplete insert statement.

        cmd.Parameters.Add(email);
        cmd.Parameters.Add(firstname);
        cmd.Parameters.Add(secondname);
        cmd.Parameters.Add(dob);
        cmd.Parameters.Add(location);
        cmd.Parameters.Add(aboutme);//add the parameter to the command
        cmd.ExecuteNonQuery(); //actually run the sql


    }

}

我尝试了这个但是我收到错误System.InvalidOperationException：ExecuteNonQuery：Connection属性尚未初始化。

我也改变了数据库，所以它不是NN（非空），看它是否有帮助，但没有快乐

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Data.Odbc;

public partial class Default2 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {

    string email = TextBox1.Text; //added variable name
    string firstname = TextBox2.Text;
    string secondname = TextBox3.Text;
    string dob = TextBox4.Text;
    string location = TextBox5.Text;
    string aboutme = TextBox6.Text;

    OdbcConnection cn = new OdbcConnection("Driver={MySQL ODBC 3.51 Driver}; Server=localhost; Database=gymwebsite; User=root; Password=;");
    cn.Open();
    OdbcCommand cmd = new OdbcCommand("INSERT INTO User(Email) VALUES('?Email')");



    cmd.Parameters.Add(new OdbcParameter("?email", email));
    cmd.ExecuteNonQuery();


    }

}

数据库中的数据是大写字母，如'L'ocation，我的字符串设置为小写。不确定它是否在我的代码中回到了前面？

-- -----------------------------------------------------

-- Table `gymwebsite`.`User`

-- -----------------------------------------------------

CREATE  TABLE IF NOT EXISTS `gymwebsite`.`User` (

  `UserID` INT NOT NULL AUTO_INCREMENT ,

  `Email` VARCHAR(245) NULL ,

  `FirstName` VARCHAR(45) NULL ,

  `SecondName` VARCHAR(45) NULL ,

  `DOB` VARCHAR(15) NULL ,

  `Location` VARCHAR(45) NULL ,

  `Aboutme` VARCHAR(245) NULL ,

  PRIMARY KEY (`UserID`) )

ENGINE = InnoDB;

INSERT INTO `gymwebsite`.`user`
(`UserID`,
`Email`,
`FirstName`,
`SecondName`,
`DOB`,
`Location`,
`Aboutme`)
VALUES
(
{UserID: INT},
{Email: VARCHAR},
{FirstName: VARCHAR},
{SecondName: VARCHAR},
{DOB: VARCHAR},
{Location: VARCHAR},
{Aboutme: VARCHAR}
);
EDIT `gymwebsite`.`user`;

Answer 1

使用此

OdbcCommand cmd = new OdbcCommand("INSERT INTO User (Email, FirstName, SecondName, DOB, Location, Aboutme) VALUES ("+ email +","+ firstname+","+SecondName+","+DOB+","+Location+","+Aboutme+")",cn);

尝试使用我之前发布的参数...并使其正常工作。

问候

Answer 2

指定此行的所有参数 -

var v1 = cmd.Parameters.Add("email",OdbcType.VarChar, , 30); v1.Value = email;

Answer 3

您需要将OdbcParameter个实例添加到参数集合中：

cmd.Parameters.Add(new OdbcParameter("email", email)); 
...

第一个参数是insert语句中参数的名称，第二个参数是用于确定DbType和内容的对象。

Answer 4

您可能还需要切换SQL命令以使用如下问号：

OdbcCommand cmd = new OdbcCommand("INSERT INTO User (Email, FirstName, SecondName, DOB, Location, Aboutme) VALUES (?, ?, ?, ?, ?, ?)");

Answer 5

你试过这个吗？

cmd.Parameters.Add(new OdbcParameter(email));

也有一些重载。

Answer 6

使用 Parameters.AddWithValue（）方法，

OdbcCommand cmd = new OdbcCommand("INSERT INTO `User` 
  (Email, FirstName, SecondName, DOB, Location, Aboutme) 
    VALUES 
     ('?Email', '?FirstName', '?SecondName', '?DOB', '?Location','?Aboutme')",cn); 

cmd.Parameters.AddWithValue("?Email", textBox1.Text);
...

试图插入mysql数据库的错误？

6 个答案: