C#、Winfrom添加数据时，防止点击多次按钮导致数据重复添加

有一个偷懒的方法，在保存按钮里面添加 button.Enable  = false;

点击保存就让他失效；

下面是正常操作，在insert之前进行select查询一下有没有结果，没有就insert，有的话提示重复

1、打开链接

 SqlConnection conn = new SqlConnection(SQL);
 conn.Open();

2、查询语句

SqlCommand cmd1 = conn.CreateCommand();
cmd1.CommandText = "select * from basicMaterial where materialId = '" + id + "'";

3、验证数据是否存在

SqlDataReader dataReader= cmd1.ExecuteReader();
 if (dataReader.HasRows)
 {
　　MessageBox.Show("已存在该记录，保存失败！");
 }

4、不存在执行添加操作

else
                {
                    dataReader.Close();
                    SqlCommand cmd = conn.CreateCommand();
                    cmd.CommandText = "insert into basicMaterial (pinName,materialId,materialName,materialSpecs) VALUES ('" + pinName + "','" + id + "','" + name + "','" + specs + "')";
                    int a = cmd.ExecuteNonQuery();
                    if (a > 0)
                    {
                        MessageBox.Show("保存成功！");
                    }
                    else
                    {
                        MessageBox.Show("保存失败！");
                    }
                }

                conn.Close();

附完整代码：

conn.Open();
                //在添加数据之前，先要验证数据是否存在，防止不小心多次点击添加按钮造成重复添加数据
                SqlCommand cmd1 = conn.CreateCommand();
                cmd1.CommandText = "select * from basicMaterial where materialId = '" + id + "'";
                SqlDataReader dataReader= cmd1.ExecuteReader();
                if (dataReader.HasRows)
                {
                    MessageBox.Show("已存在该记录，保存失败！");
                }
                else
                {
                    dataReader.Close();
                    SqlCommand cmd = conn.CreateCommand();
                    cmd.CommandText = "insert into basicMaterial (pinName,materialId,materialName,materialSpecs) VALUES ('" + pinName + "','" + id + "','" + name + "','" + specs + "')";
                    int a = cmd.ExecuteNonQuery();
                    if (a > 0)
                    {
                        MessageBox.Show("保存成功！");
                    }
                    else
                    {
                        MessageBox.Show("保存失败！");
                    }
                }

                conn.Close();