SaveChanges方法不是将数据插入数据库，而是在删除时有效

Question

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上述代码中的EmployeeDbContex contex = new EmployeeDbContex(); tbl_Employee Employee = new tbl_Employee(); Employee.Name = txtname.Text.Trim(); Employee.Address = txtAddress.Text.Trim(); Employee.Salary = Convert.ToDecimal(txtSalary.Text.Trim()); Employee.Gender = ddGender.SelectedItem.Text; Employee.ContactNo = txtContact.Text.Trim(); contex.tbl_Employee.Add(Employee); contex.SaveChanges(); 方法无效。这些值分配给属性，但在插入新数据时不会在数据库中进行更改。

然而，当我执行删除时，它完美无缺。当我在调试模式下检查程序时，控件只是通过SaveChanges()方法，并没有跳转到此方法的定义。