将整数和字符串插入 SQL 服务器数据库 c# 的问题

Question

我无法将整数值 [Question Type] 和字符串 [Question Space] 同时插入数据库的同一行。每当我单击按钮并尝试执行时，都会出现一个错误：

An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll

Additional information: Incorrect syntax near '('.

代码：

SqlCommand command5 = new SqlCommand("INSERT INTO ([Question Space], [Question Type]) Questions VALUES ('@QuestionText', '@checkedradiobutton')", connect);
command5.Parameters.AddWithValue("@QuestionText", QuestionText);
command5.Parameters.AddWithValue("@checkedradiobutton", checkedradiobutton);

command5.ExecuteNonQuery();

如果有人能给我任何帮助，我将不胜感激。

如果你想看，这里是按钮的完整代码：

private void button1_Click(object sender, EventArgs e)
{
    string connectionString = ConfigurationManager.ConnectionStrings["myconnectionstring"].ConnectionString;

    SqlConnection connect = new SqlConnection(connectionString);
    connect.Open();

    int checkedradiobutton = 0;
        
    if(radioButton1.Checked)
    {
        checkedradiobutton = 1;
    }
    else if(radioButton2.Checked)
    {
        checkedradiobutton = 2;
    }
    else if(radioButton3.Checked)
    {
        checkedradiobutton = 3;
    }

    string QuestionText = QuestionBox.Text;

    SqlCommand command5 = new SqlCommand("INSERT INTO ([Question Space], [Question Type]) Questions VALUES ('@QuestionText', '@checkedradiobutton')", connect);
    command5.Parameters.AddWithValue("@QuestionText", QuestionText);
    command5.Parameters.AddWithValue("@checkedradiobutton", checkedradiobutton);

    command5.ExecuteNonQuery();
}

还有我的数据库table：

CREATE TABLE [dbo].[Questions] 
(
     [QuestionID]     INT           IDENTITY (1, 1) NOT NULL,
     [Actual answer]  NVARCHAR (50) NULL,
     [Question Space] NVARCHAR (50) NULL,
     [Question Type]  INT           NULL,

     PRIMARY KEY CLUSTERED ([QuestionID] ASC)
);

Answer 1

您不必在查询中用 ' 包装参数。开始清洁它，看看它是否有效

    SqlCommand command5 = new SqlCommand("INSERT INTO [dbo].[Questions] ([Question Space], [Question Type]) Questions VALUES (@QuestionText, @checkedradiobutton)", connect);
    command5.Parameters.AddWithValue("@QuestionText", QuestionText);
    command5.Parameters.AddWithValue("@checkedradiobutton", checkedradiobutton);


    command5.ExecuteNonQuery();

Answer 2

INSERT INTO 的正确语法是

INSERT INTO <table> (field1, field2, fieldN) VALUES (value1, value2, valueN)

所以你的命令应该写成

SqlCommand command5 = new SqlCommand(@"INSERT INTO Questions  
                        ([Question Space], [Question Type]) VALUES  
                        (@QuestionText, @checkedradiobutton)", connect);

请注意参数占位符不应包含在单引号中，因为这样做会将它们转换为文字文本。（在 [Question Space] 字段中插入 "@QuestionText" 字符串）

最后，尽量避免使用 AddWithValue，这是一个有很多缺点的快捷方式，您可以在 Can we stop using AddWithValue already and in How Data Access Code Affects Database Performance

中阅读

这还是一行代码

 command5.Parameters.Add("@QuestionText", SqlDbType.NVarChar).Value = QuestionText;

Answer 3

INSERT语法错误，table的名字应该在"INSERT INTO"之后，例如：

INSERT INTO table_name (column1,column2,column3,...)
VALUES (value1,value2,value3,...);

干杯。

将整数和字符串插入 SQL 服务器数据库 c# 的问题

Issue with Inserting integer and string into SQL Server database c#

c#

database

sql-server

sql-insert