Question

我必须使用insert query在表中插入值...存储在数据库中的表有3列：1。Date（DateTime）2。SensorValue（Float）3。差异（Float）现在每列的值来自datagridview .....这里是插入按钮的代码

con.ConnectionString = "Data Source=.\\SQLEXPRESS;AttachDbFilename=C:\\dbsave.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True";
if (con.State == ConnectionState.Closed)
{
    con.Open();
}
for (Int32 i = 0; i < dataGridView1.Rows.Count-1; i++)
{
    String query1 = 
        "INSERT INTO " + tbName + 
        " ( Date, SensorValue, Difference) " + "VALUES (" +     
        dataGridView1.Rows[i].Cells[0].Value + "," + 
        dataGridView1.Rows[i].Cells[1].Value + "," + 
        dataGridView1.Rows[i].Cells[2].Value + ")";
    SqlCommand cmd1 = new SqlCommand(query1, con);
    cmd1.ExecuteNonQuery();
}
con.Close();
MessageBox.Show("The table has been saved");

执行查询时出错... ....日期列中的第一个条目是值：12/05/2012 14:32:00 ....所以基本上sql不接受冒号放在14 ....我怎么能解决这个问题？请帮忙

Answer 1

更新您的查询并添加撇号：

String query1 = 
    "INSERT INTO " + tbName + 
    " ( Date, SensorValue, Difference) " + "VALUES ('" +     
    dataGridView1.Rows[i].Cells[0].Value + "'," + 
    dataGridView1.Rows[i].Cells[1].Value + "," + 
    dataGridView1.Rows[i].Cells[2].Value + ")";
SqlCommand cmd1 = new SqlCommand(query1, con);

但我同意Liath，参数更安全。

Answer 2

该代码甚至无法编译，因此无法给出运行时错误。

这里你的引号太多了：

String query1 = "INSERT INTO " + tbName + " (" Date, Sensor...

应该是：

String query1 = "INSERT INTO " + tbName + " ( Date, Sensor...

当你有一个日期时间值时，你需要它周围的撇号：

...LUES (" + dataGridView1.Rows[i].Cells[0].Value + "," + ...

应该是：

...LUES ('" + dataGridView1.Rows[i].Cells[0].Value + "'," + ...

Answer 3

尝试使用参数化查询。像这样：

string query = "INSERT INTO table (Date, SensorValue, Differences) VALUES (@Date, @SensorValue, @Differences)";            
var command = new SqlCommand(query, con);
command.Parameters.Add(new SqlParameter("@Date", System.Data.SqlDbType.DateTime));
command.Parameters.Add(new SqlParameter("@SensorValue", System.Data.SqlDbType.Float));
command.Parameters.Add(new SqlParameter("@Differences", System.Data.SqlDbType.Float));
for (int i = 0; i < dataGridView1.Rows.Count-1; i++)
{
    command.Parameters["@Date"].Value = Convert.ToDateTime(dataGridView1.Rows[i].Cells[0].Value);
    command.Parameters["@SensorValue"].Value = Convert.ToDecimal(dataGridView1.Rows[i].Cells[1].Value);
    command.Parameters["@Differences"].Value = Convert.ToDecimal(dataGridView1.Rows[i].Cells[2].Value);
    command.ExecuteNonQuery();
}

Answer 4

虽然我很难推荐使用参数，但是在没有看到所有变量的情况下很难诊断出来。它不仅会使这类问题更容易被发现，而且还可以保护您免受SQL注入攻击。

错误：'14'附近的语法不正确

4 个答案: