我有一个问题，我似乎无法弄清楚。我正在创建一个添加客户信息的应用程序，然后将其与正在提供的服务相关联。我在 xampp 数据库中创建了两个表之间的关系。这些表是 tclientinfo 和 tserviceinfo。tclientinfo 表中的列是 Client_ID(PK)、First_Name、Last_Name、Phone 和 Email。在 tserviceinfo 中，Service_Order、Date、Tech、Brand、Model、OS、Type、PC_Issue、Service、Service_Price、Total_Price、Service_Notes、Client_ID。Client_ID 是我使用的关系，但我无法将信息添加到 tserviceinfo 表。我收到 SQL 异常：无法添加或更新子行：外键约束失败（'dbocomputerinformation'.'tserviceinfo',CONSTRAINT 'tserviceinfo_ibfk_3'
我将信息插入 tclientinfo 的添加按钮是：
private void btnAdd_Click(object sender, EventArgs e) { MySqlConnection conn = new MySqlConnection("server=localhost;uid=root;password=Passwordwhatever;database=dbocomputerinformation;"); conn.Open();
string email = tbEmail.Text;
string date = tbDate.Text;
//try statement for validation before sending to database.
try
{
if (tbFirstName.Text.Length == 0)
{
MessageBox.Show("Please enter in customer's first name.");
this.tbFirstName.Focus();
return;
}
if (tbLastName.Text.Length == 0)
{
MessageBox.Show("Please enter in customer's last name.");
this.tbLastName.Focus();
return;
}
if (tbPhone.Text.Length < 10)
{
MessageBox.Show("Phone number must be ten digits.");
this.tbPhone.Focus();
return;
}
if (tbPhone.Text.Length == 0)
{
MessageBox.Show("Please enter in customer's phone number.");
this.tbPhone.Focus();
return;
}
if (tbPhone.Text != string.Empty && !Regex.IsMatch(tbPhone.Text, @"^[0-9]+$"))
{
MessageBox.Show("Please enter in numbers only.");
this.tbPhone.Focus();
return;
}
if (tbEmail.Text.Length == 0)
{
MessageBox.Show("Please enter in customer's email.");
this.tbEmail.Focus();
return;
}
if (email.IndexOf('@') == -1 || email.IndexOf('.') == -1)
{
MessageBox.Show("Please enter a valid email address.");
this.tbEmail.Focus();
return;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
try
{
MySqlCommand command = new MySqlCommand("Insert into tclientinfo (First_Name, Last_Name, Phone, Email) values (?First_Name, ?Last_Name, ?Phone, ?Email)", conn);
command.Parameters.AddWithValue("?First_Name", tbFirstName.Text);
command.Parameters.AddWithValue("?Last_Name", tbLastName.Text);
command.Parameters.AddWithValue("?Phone", tbPhone.Text);
command.Parameters.AddWithValue("?Email", tbEmail.Text);
command.ExecuteNonQuery();
conn.Close();
MessageBox.Show("Client Added Successfully.");
}
catch (MySqlException ex)
{
MessageBox.Show("Can't connect to database\n" + ex.ToString());
}
}
然后我插入 tserviceinfo 是：
private void btnCreate_Click(object sender, EventArgs e) { //string connString = "server=localhost;uid=root;password=Passwordwhatever;database=dbocomputerinfo;"; MySqlConnection conn = new MySqlConnection("server=localhost;uid=root;password=Passwordwhatever;database=dbocomputerinfo;"); conn.Open();
string date = tbDate.Text;
//try statement for validation before sending to database.
try
{
if (tbDate.Text.Length == 0)
{
MessageBox.Show("Please enter in date of service.");
this.tbDate.Focus();
return;
}
if (date.IndexOf('-') == -2)
{
MessageBox.Show("Please enter correct date. mm-dd-yy.");
this.tbDate.Focus();
return;
}
if (tbTech.Text.Length == 0)
{
MessageBox.Show("Please enter in service technician.");
this.tbTech.Focus();
return;
}
if (tbBrand.Text.Length == 0)
{
MessageBox.Show("Please enter in customer's brand of computer.");
this.tbBrand.Focus();
return;
}
if (tbModel.Text.Length == 0)
{
MessageBox.Show("Please enter in computer model.");
this.tbModel.Focus();
return;
}
if (tbOS.Text.Length == 0)
{
MessageBox.Show("Please enter in computer's operating system.");
this.tbOS.Focus();
return;
}
if (rbDesktop.Checked == false && rbNotebook.Checked == false)
{
MessageBox.Show("Please select device type.");
this.rbDesktop.Focus();
return;
}
if (lvOrdered.Items.Count == 0)
{
MessageBox.Show("Please select a service.");
this.lvServices.Focus();
return;
}
if (tbIssue.Text.Length == 0)
{
MessageBox.Show("Please describe the issue with the computer.");
this.tbIssue.Focus();
return;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
try
{
MySqlCommand command = new MySqlCommand("Insert into tserviceinfo (Date, Tech, Brand, Model, OS, Type, PC_Issue, Service, Service_Price, Total_Price) values (?Date, ?Tech, ?Brand, ?Model, ?OS, ?Type, ?PC_Issue, ?Service, ?Service_Price, ?Total_Price)", conn);
command.Parameters.AddWithValue("?Date", tbDate.Text);
command.Parameters.AddWithValue("?Tech", tbTech.Text);
command.Parameters.AddWithValue("?Brand", tbBrand.Text);
command.Parameters.AddWithValue("?Model", tbModel.Text);
command.Parameters.AddWithValue("?OS", tbOS.Text);
command.Parameters.AddWithValue("?PC_Issue", tbIssue.Text);
/**
* Was having issues inserting a single service, it would dublicate itself in the db, this was the solution
* this adds just a single service with nothing else, and it reads back properly as well.
**/
if (lvOrdered.Items.Count == 1)
{
string singleService = string.Join(" ", services);
command.Parameters.AddWithValue("?Service", singleService);
}
else
{
/**
* Combine all the services into one string seperated by commas
* and add that to the database
* */
string serviceList = string.Join(", ", services);
command.Parameters.AddWithValue("?Service", serviceList);
}
/**
* Combine all the prices into one string seperated by commas
* and add that to the database
* */
string servicePriceList = string.Join(", ", servicePrice);
command.Parameters.AddWithValue("?Service_Price", servicePriceList);
command.Parameters.AddWithValue("?Total_Price", lblPrice.Text);
//clears lists so dublicates don't happen when creating more work orders than just 1.
services.Clear();
servicePrice.Clear();
if (rbDesktop.Checked)
{
command.Parameters.AddWithValue("?Type", "Desktop");
}
else if (rbNotebook.Checked)
{
command.Parameters.AddWithValue("?Type", "Notebook");
}
command.ExecuteNonQuery();
conn.Close();
tbFirstName.Clear();
tbLastName.Clear();
tbDate.Clear();
tbEmail.Clear();
tbBrand.Clear();
tbIssue.Clear();
tbTech.Clear();
tbModel.Clear();
tbPhone.Clear();
tbOS.Clear();
lvOrdered.Items.Clear();
lblPrice.Text = "$0.00";
}
catch (MySqlException ex)
{
MessageBox.Show("Can't connect to database\n" + ex.ToString());
}
}
所以不用说，我不知道从这里做什么。任何帮助都会很棒或任何想法。如果您需要更多信息，请告诉我。谢谢！