问题描述

这是我保存文件的按钮:

This is my button to save file:

private void metroButton12_Click(object sender, EventArgs e) // save
{
    DataSet ds = (DataSet)dataGridView1.DataSource;
    SaveFileDialog sfd = new SaveFileDialog();
    sfd.Filter = "XML|*.xml";
    if (sfd.ShowDialog() == DialogResult.OK)
    {
        try
        {
            ds.Tables[0].WriteXml(sfd.FileName);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }
    }
}

我尝试将我的 datagridview 保护为 XML，但当我选择文件时没有任何事情发生.当我启动控制台时，我看到了这个:System.NullReferenceException:对象引用未设置为对象实例.

I try to safe my datagridview to XML but nothing happpend when I choose file. When I start console I see this: System.NullReferenceException: The object reference was not set to an object instance.

我的网格视图看起来像:身份证名称1 迈克尔2 菜鸟

My gridview look like: ID Name 1 Michale 2 Noob

我在这里做错了什么?.. 我在网上看到了很多东西，但在 stackoverflow 和其他论坛中找不到任何解决方案.新手请耐心等待.谢谢！

What am I doing here wrong?.. I saw a lot of thing's on the web but could not find any solutions in stackoverflow and other forums. Please be patient for newbie guys. Thank you!

推荐答案

在我看来，你的问题不是你想的那样.

To me it sounds like your problem is not where you think it is.

当我启动控制台时，我看到:System.NullReferenceException:对象引用未设置为对象实例.

when i start console i see this : System.NullReferenceException: The object reference was not set to an object instance.

对我来说，您的意思是您在启动应用程序时收到消息，而不是在单击按钮时收到消息.如果您在单击之前收到错误，则您的问题在其他地方，而不是在您发布的代码段中.这是您当前正在执行的完整且可测试的代码段.

To me you are implying that you get the message when you launch the application, not when you click the button. If you get the error before you click, your problem is elsewhere and not in the code snippet you posted. Here is a complete and testable snippet of what you are currently doing.

using System;
using System.Data;
using System.Windows.Forms;

namespace DataGridViewToXML_43053387
{
    public partial class Form1 : Form
    {
        //DataSet theDataSet;
        public Form1()
        {
            InitializeComponent();
            InsertDgvIntoForm();
            ExportDgvToXML();
        }

        private void InsertDgvIntoForm()
        {
            //create a data set
            DataSet ds = new DataSet();
            //create a data table for the data set
            DataTable dt = new DataTable();
            //create some columns for the datatable
            DataColumn dc = new DataColumn("ItemName");
            DataColumn dc2 = new DataColumn("ItemValue");
            DataColumn dc3 = new DataColumn("Blah");
            DataColumn dc4 = new DataColumn("Bleh");
            //add the columns to the datatable
            dt.Columns.Add(dc);
            dt.Columns.Add(dc2);
            dt.Columns.Add(dc3);
            dt.Columns.Add(dc4);

            //create 5 rows of irrelevant information
            for (int i = 0; i < 5; i++)
            {
                DataRow dr = dt.NewRow();
                dr["ItemName"] = "Item" + i + "Name";
                dr["ItemValue"] = "Item" + i + "Value";
                dr["Blah"] = "Item" + i + "Blah";
                dr["Bleh"] = "Item" + i + "Bleh";
                dt.Rows.Add(dr);
            }
            //add the datatable to the datasource
            ds.Tables.Add(dt);
            //just because it looks better on my screen
            dataGridView1.AutoSize = true;
            //make this data the datasource of our gridview
            dataGridView1.DataSource = ds.Tables[0];

        }

        private void ExportDgvToXML()
        {
            DataTable dt = (DataTable)dataGridView1.DataSource;
            SaveFileDialog sfd = new SaveFileDialog();
            sfd.Filter = "XML|*.xml";
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                try
                {
                    dt.WriteXml(sfd.FileName);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex);
                }
            }
        }
    }
}

这篇关于c# 将DataGridView保存到Xml文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！