简体   繁体   English

在实体框架中将数据表更新为多个表

[英]Updating datatable to multiple tables in entity framework

I have created a method to add data from a datatable to a table in my database via entity framework, however it only allows me to populate one table and I want to populate multiple tables within the one method. 我创建了一种方法,可以通过实体框架将数据表中的数据从数据表添加到数据库中的表中,但是它只允许我填充一个表,而我想在一个方法中填充多个表。

Below is my method adding to the student table and I have commented out the module table because when I add this in no data is transferred to the database. 以下是我添加到学生表中的方法,并且我注释掉了模块表,因为当我添加此表时,没有数据传输到数据库。 Can someone recommend a way I can populate multiple tables within this method? 有人可以推荐一种可以在此方法中填充多个表的方法吗?

Thanks 谢谢

public Boolean ConvertDataTable(DataTable tbl)
    {
        string Feedback = string.Empty;
        ModuleEntities db = new ModuleEntities();
        // iterate over your data table
        foreach (DataRow row in tbl.Rows)
        {

            student st = new student();
            st.student_no = row.ItemArray.GetValue(0).ToString();
            st.surname = row.ItemArray.GetValue(1).ToString();
            st.firstname = row.ItemArray.GetValue(2).ToString();
            db.students.Add(st);
            //module mod = new module();
            //mod.module_code = row.ItemArray.GetValue(3).ToString();
            //mod.name = row.ItemArray.GetValue(4).ToString();
            //db.modules.Add(mod);


        }
        try
        {
            db.SaveChanges();
            Feedback = "Upload Successful";
            return true;
        }
        catch
        {
            Feedback = "Upload Failed";
            return false;
        }

    }

Student Class 学生班

public partial class student
{
    public student()
    {
        this.submits = new HashSet<submit>();
        this.takes = new HashSet<take>();
        this.lecturers = new HashSet<lecturer>();
    }

    public string student_no { get; set; }
    public string surname { get; set; }
    public string firstname { get; set; }

    public virtual ICollection<submit> submits { get; set; }
    public virtual ICollection<take> takes { get; set; }
    public virtual ICollection<lecturer> lecturers { get; set; }
}

Module Class 模块类别

public partial class module
{
    public module()
    {
        this.takes = new HashSet<take>();
        this.lecturers = new HashSet<lecturer>();
    }

    public string module_code { get; set; }
    public string name { get; set; }

    public virtual ICollection<take> takes { get; set; }
    public virtual ICollection<lecturer> lecturers { get; set; }
}

Take Class 上课

public partial class take
{
    public string student_no { get; set; }
    public string module_code { get; set; }
    public string grade { get; set; }

    public virtual module module { get; set; }
    public virtual student student { get; set; }
}

Here's the gist of adding related data to database using Entity Framework: 这是使用实体框架向数据库添加相关数据的要点:

class Program
{
    static void Main(string[] args)
    {
        SchoolDBEntities dataContext = new SchoolDBEntities();
        //Create student object
        Student student1 = new Student();
        student1.StudentName = "Student 01";
        //Create course objects
        Cours mathCourse = new Cours();
        mathCourse.CourseName = "Math";
        Cours scienceCourse = new Cours();
        scienceCourse.CourseName = "Science";
        //Save courses to student 1
        student1.Courses.Add(mathCourse);
        student1.Courses.Add(scienceCourse);
        //Save related data to database
        //This will automatically populate join table
        //between Students and Courses
        dataContext.Students.Add(student1);
        dataContext.SaveChanges();
    }
}

Another illustration: 另一个例证: 在此处输入图片说明

声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM