Question

学生表中的

我只希望复制用户表中的学生用户，并且在教师表中我只希望从用户表中复制教师用户。如何为此问题格式化新循环。谢谢。

以下是代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data;
using System.Web.UI;
using System.Data.OleDb;
using System.Web.UI.WebControls;

public partial class BulkUser : System.Web.UI.Page
{
    DataTable Gendt = new DataTable();
    DataTable Usersdt = new DataTable();
    DataTable Studentsdt = new DataTable();
    DataTable Facultydt = new DataTable();


    protected void Page_Load(object sender, EventArgs e)
    {

    }


    protected void UsersGridView_DataBinding(object sender, EventArgs e)
    {
        UsersGridView.DataSource = Gendt;
    }


    protected void StudentsGridView_DataBinding(object sender, EventArgs e)
    {
        StudentsGridView.DataSource = Studentsdt;
    }

    protected void FacultyGridView_DataBinding(object sender, EventArgs e)
    {
        FacultyGridView.DataSource = Facultydt;
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        OleDbConnection cnn = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Server.MapPath(@"~\data\University.xlsx") + "; Extended Properties=Excel 12.0;");
        OleDbCommand oconn = new OleDbCommand("select * from [Sheet1$]", cnn);
        cnn.Open();
        OleDbDataAdapter adp = new OleDbDataAdapter(oconn);
        adp.Fill(Gendt);
        cnn.Close();


        Usersdt = Gendt.Copy();
        Studentsdt = Gendt.Copy();
        Studentsdt.Columns.Remove("UserType");

        Facultydt = Studentsdt.Copy();

        //foreach (DataRow dr in Usersdt.Rows)
        //{
        //    foreach (DataRow dr1 in Studentsdt.Rows)
        //    {

        //        ////if (dr["UserType"].ToString().Contains("student"))
        //        //    Studentsdt.ImportRow(Student); 
        //    }

        UsersGridView.DataBind();
        StudentsGridView.DataBind();
        FacultyGridView.DataBind();
    }
}

Answer 1

您可以按照此逻辑搜索UsersTable，并根据列值将整行（最后一列除外）复制到目标表。 此方法在遍历UsersTable时具有更好的性能。

foreach(DataRow dRow in Usersdt.Rows)
{
    DataTable destinationTable = null;

    if (dRow.Field<string>("UserType") == "student")
        destinationTable = Studentsdt;
    else if (dRow.Field<string>("UserType") == "Faculty")
        destinationTable = Facultydt;
    else
        continue; // skip the current row

    // copy the row skipping the last column as required
    object[] rowData = new object[dRow.ItemArray.Length - 1];
    Array.ConstrainedCopy(dRow.ItemArray, 0, rowData, 0, rowData.Length);
    destinationTable.Rows.Add(rowData);
}

Answer 2

假设您的数据位于Usersdt，那么您需要将其过滤为

DataRow[] studentRows= Usersdt.Select("UserType=student");
DataRow[] facultyRows= Usersdt.Select("UserType=Faculty");

// import filtered rows in student and faculty tables one by one
foreach (DataRow row in studentRows) 
{
   Studentdt.ImportRow(row);
}
foreach (DataRow row in facultyRows) 
{
   Facultydt.ImportRow(row);
}

如何根据特定数据行将特定行从一个数据表复制到另一个数据表

2 个答案: