c# - Web 表单在数据库中两次上传相同的数据

Question

我正在将数据上传到数据库，但是我的表单首先在数据库中上传了相同的数据两次我上传数据时没有检查是否插入了天气它工作正常它正在上传数据一次现在我已经检查了如果data inserted than show the message data inserted successful but this is upload data twice.

这是我的代码:

SqlConnection conn1 = new SqlConnection("Data Source=ZAZIKHAN\\SQLEXPRESS;Initial Catalog=resume;Integrated Security=True");
conn1.Open();

SqlCommand cmd3 = new SqlCommand("insert into Profile(Id,Name,JobTitle,Phone,Email,Address,Website,Facebook,Twitter,GooglePlus,Skype,Picture,WhyMeText) values('"+ID.Text+"','" + TextBox1.Text + "','" + TextBox2.Text + "','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','" + TextBox6.Text + "','" + TextBox7.Text + "','" + TextBox8.Text + "','" + TextBox9.Text + "','" + TextBox10.Text + "','" + uploadFolderPath + "','" + TextArea1.InnerText + "')", conn1);

cmd3.ExecuteNonQuery();
if (cmd3.ExecuteNonQuery() == 1)
{
        Response.Write("<script LANGUAGE='JavaScript' >alert('information saved Successful')</script>");
        TextBox1.Text = "";
        TextBox2.Text = "";
        TextBox3.Text = "";
        TextBox4.Text = "";
        TextBox5.Text = "";
        TextBox6.Text = "";
        TextBox7.Text = "";
        TextBox8.Text = "";
        TextBox9.Text = "";
        TextBox10.Text = "";
        TextArea1.InnerText = "";
}
else { Response.Write("<script LANGUAGE='JavaScript' >alert('sorry try again')</script>"); }

conn1.Close();

Answer 1

因为您执行了 SqlCommand 两次。

一个是用

cmd3.ExecuteNonQuery();

还有一个是with；

if (cmd3.ExecuteNonQuery() == 1)

来自 MSDN ;

Executes a Transact-SQL statement against the connection and returns the number of rows affected.

请始终使用 parameterized queries .这种字符串连接对于 SQL Injection 是开放的攻击。

也可以使用 using处理你的 SqlConnection 的语句；

using(SqlConnection conn1 = new SqlConnection("Data Source=ZAZIKHAN\\SQLEXPRESS;Initial Catalog=resume;Integrated Security=True"))
{
    //Write here your command with parameterized way..
    conn1.Open();
    if (cmd3.ExecuteNonQuery() == 1)
    {
      //....
    }
}