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C中“我的导出”按钮(btnExport)的更改#

export datatable csv html c#

-1

Evan Tan · 技术社区 · 7 年前

这是我的代码,用于将一个简单的Datatable导出到CSV文件程序。我的程序实际上是运行一个网站来存储数据库并将数据库转换为 .csv 使用“导出”按钮创建文件。

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Contact : System.Web.UI.Page
{

    SqlConnection sqlCon = new SqlConnection(@"Data Source= DESKTOP-25V3I8O;Initial Catalog=ASPCRUD;Integrated Security=true");
    DataTable dtbl = new DataTable();

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            btnDelete.Enabled = false;
            FillGridView();
        }
    }

    protected void btnClear_Click(object sender, EventArgs e)
    {
        Clear();
    }

    public void Clear()
    {
        hfContactID.Value = "";

        txtName.Text = txtMobile.Text = txtAddress.Text = txtPostcode.Text = "";
        lblSuccessMessage.Text = lblErrorMessage.Text = "";
        btnSave.Text = "Save";
        btnDelete.Enabled = false;
    }

    protected void btnSave_Click(object sender, EventArgs e)
    {
        if (sqlCon.State == ConnectionState.Closed)
            sqlCon.Open();
        SqlCommand sqlCmd = new SqlCommand("ContactCreateOrUpdate", sqlCon);
        sqlCmd.CommandType = CommandType.StoredProcedure;
        sqlCmd.Parameters.AddWithValue("@ContactID",(hfContactID.Value==""?0:Convert.ToInt32(hfContactID.Value)));
        sqlCmd.Parameters.AddWithValue("@Name", txtName.Text.Trim());
        sqlCmd.Parameters.AddWithValue("@Mobile", txtMobile.Text.Trim());
        sqlCmd.Parameters.AddWithValue("@Address", txtAddress.Text.Trim());
        sqlCmd.Parameters.AddWithValue("@Postcode", txtPostcode.Text.Trim());
        sqlCmd.ExecuteNonQuery();
        sqlCon.Close();
        string ContactID = hfContactID.Value;
        Clear();
        if (ContactID=="")
            lblSuccessMessage.Text = "Saved Successfully";
        else
            lblSuccessMessage.Text = "Updated Successfully";

        FillGridView();
    }

    void FillGridView()
    {
        if (sqlCon.State == ConnectionState.Closed)
            sqlCon.Open();
        SqlDataAdapter sqlData = new SqlDataAdapter("ContactViewAll", sqlCon);
        sqlData.SelectCommand.CommandType = CommandType.StoredProcedure;    
        sqlData.Fill(dtbl);
        sqlCon.Close();
        gvContact.DataSource = dtbl;
        gvContact.DataBind();
    }

    protected void lnk_OnClick(object sender, EventArgs e)
    {
        int ContactID = Convert.ToInt32((sender as LinkButton).CommandArgument);
        if (sqlCon.State == ConnectionState.Closed)
            sqlCon.Open();
        SqlDataAdapter sqlData = new SqlDataAdapter("ContactViewByID", sqlCon);
        sqlData.SelectCommand.CommandType = CommandType.StoredProcedure;
        sqlData.SelectCommand.Parameters.AddWithValue("@ContactID", ContactID);
        sqlData.Fill(dtbl);
        sqlCon.Close();
        hfContactID.Value = ContactID.ToString();
        txtName.Text = dtbl.Rows[0]["Name"].ToString();
        txtMobile.Text = dtbl.Rows[0]["Mobile"].ToString();
        txtAddress.Text = dtbl.Rows[0]["Address"].ToString();
        txtPostcode.Text = dtbl.Rows[0]["Postcode"].ToString();
        btnSave.Text = "Update";
        btnDelete.Enabled = true;
    }


    protected void btnDelete_Click(object sender, EventArgs e)
    {
        if (sqlCon.State == ConnectionState.Closed)
            sqlCon.Open();
        SqlCommand sqlCmd = new SqlCommand("ContactDeleteByID", sqlCon);
        sqlCmd.CommandType = CommandType.StoredProcedure;
        sqlCmd.Parameters.AddWithValue("ContactID", Convert.ToInt32(hfContactID.Value));
        sqlCmd.ExecuteNonQuery();
        sqlCon.Close();
        Clear();
        FillGridView();
        lblSuccessMessage.Text = "Deleted Successfully";
    }

    protected void ExportDataTableToCSV()
    {
        Response.Clear();
        Response.ContentType = "text/csv";
        Response.AddHeader("content-disposition", "attachment;filename=UserDetails.csv");

        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < dtbl.Columns.Count; i++)
        {
            sb.Append(dtbl.Columns[i].ColumnName + ',');
        }
        sb.Append(Environment.NewLine);

        for (int j = 0; j < dtbl.Rows.Count; j++)
        {
            for (int k = 0; k < dtbl.Columns.Count; k++)
            {
                sb.Append(dtbl.Rows[j][k].ToString() + ',');
            }
            sb.Append(Environment.NewLine);
        }
        Response.Write(sb);
        Response.Flush();
        Response.End();
    }


    protected void btnExport_Click(object sender, EventArgs e)
    {
        ExportDataTableToCSV();
    }
}

我的程序还有一个专为数据输入页设计的页面。它包含 Name , Address , Mobile 和 Postcode . 它有一个由系统自动生成的用户帐号。

1 回复 | 直到 7 年前

Xavave 7 年前

当您单击export按钮时,会发生回发,您会丢失datatable的内容,所以只需尝试删除:

if (!IsPostBack)

因此,它将是:

 protected void Page_Load(object sender, EventArgs e)
{
        btnDelete.Enabled = false;
        FillGridView();

}

以下是基于您的代码的工作示例:

 DataTable table = new DataTable();

    protected void Page_Load(object sender, EventArgs e)
    {

            table.Columns.Add("Dosage", typeof(int));
            table.Columns.Add("Drug", typeof(string));
            table.Columns.Add("Patient", typeof(string));
            table.Columns.Add("Date", typeof(DateTime));

            // Here we add five DataRows.
            table.Rows.Add(25, "Indocin", "David", DateTime.Now);
            table.Rows.Add(50, "Enebrel", "Sam", DateTime.Now);
            table.Rows.Add(10, "Hydralazine", "Christoff", DateTime.Now);
            table.Rows.Add(21, "Combivent", "Janet", DateTime.Now);
            table.Rows.Add(100, "Dilantin", "Melanie", DateTime.Now);

    }



    protected void ExportDataTableToCSV()
    {
        Response.Clear();
        Response.ContentType = "text/csv";
        Response.AddHeader("content-disposition", "attachment;filename=UserDetails.csv");

        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < table.Columns.Count; i++)
        {
            sb.Append(table.Columns[i].ColumnName + ',');
        }
        sb.Append(Environment.NewLine);

        for (int j = 0; j < table.Rows.Count; j++)
        {
            for (int k = 0; k < table.Columns.Count; k++)
            {
                sb.Append(table.Rows[j][k].ToString() + ',');
            }
            sb.Append(Environment.NewLine);
        }
        Response.Write(sb);
        Response.Flush();
        Response.End();
    }


    protected void btnExport_Click(object sender, EventArgs e)
    {
        ExportDataTableToCSV();
    }