数据库表没有更新c#
本文关键字:更新 数据库 | 更新日期: 2023-09-27 17:58:08
我有表单和dataGridView连接到数据库中的表,当我添加记录时,它显示在dataGridView中,但当我停止运行时,表返回空!
这是代码:
string employeeName = "person";
string employeeUserName ="person1";
string emplpyeeNotes = "empty";
string employeePassword = "123";
int employeeSalary = 4000;
try
{
SqlConnection cn = new SqlConnection(Properties.Settings.Default.StudentManagementDBConnectionString);
cn.Open();
string sql = "INSERT INTO Employee (Name,Salary,UserName,Password,Notes) VALUES(@name, @salary, @userName, @password, @notes)";
SqlCommand exsql = new SqlCommand(sql, cn);
exsql.Parameters.AddWithValue("@name", employeeName);
exsql.Parameters.AddWithValue("@salary", employeeSalary);
exsql.Parameters.AddWithValue("@userName", employeeUserName);
exsql.Parameters.AddWithValue("@password", employeePassword);
exsql.Parameters.AddWithValue("@notes", emplpyeeNotes);
exsql.ExecuteNonQuery();
MessageBox.Show("employee added Successfully", "", MessageBoxButtons.OK, MessageBoxIcon.Information);
this.employeeTableAdapter.Fill(this.studentManagementDBDataSet.Employee);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
试着使用这样的参数化查询:
string employeeName = textBoxName.Text;
string employeeUserName = textBoxUserName.Text;
string emplpyeeNotes = richTextBoxNotes.Text;
string employeePassword = textBoxPassword.Text;
SqlConnection cn = new SqlConnection(global::StudentManagementProject.Properties.Settings.Default.StudentManagementDBConnectionString);
try
{
string sql = "INSERT INTO Employee (Name,Salary,UserName,Password,Notes) VALUES(@name, @salary, @userName, @password, @notes)";
SqlCommand exsql = new SqlCommand(sql, cn);
cn.Open();
exsql.Parameters.AddWithValue("@name", employeeName);
exsql.Parameters.AddWithValue("@salary", 2000);
exsql.Parameters.AddWithValue("@userName", employeeUserName);
exsql.Parameters.AddWithValue("@password", employeePassword);
exsql.Parameters.AddWithValue("@notes", emplpyeeNotes);
int result=exsql.ExecuteNonQuery();
if (result > 0 )
{
MessageBox.Show("employee added Successfully", "", MessageBoxButtons.OK, MessageBoxIcon.Information);
}else
{
MessageBox.Show("employee insertion failed", "", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
finally
{
cn.Close();
}
您的数据库正在更新,但visual studio没有将您的数据库从"Solution"目录复制到"Debug"或"Bin"目录。如果你转到"调试"目录并从那里打开数据库文件,你会看到那里的更改
解决方法是更改连接字符串,并通过从数据集的属性中复制它来将其设置为mdf文件的路径。