如何继续添加到表单上的现有文本框？输入，保存，清除和重复？ [英] How to keep adding to exsiting textbox on a form? input, save, clear and repeat?
问题描述
使用System.Collections.Generic;
使用System.ComponentModel;
使用System.Data;
使用System.Drawing;
使用System.Linq;
使用System.Text;
使用System.Threading.Tasks;
使用System .Windows.Forms;
使用System.IO;
名称空间Angie_assignment
{
公共部分类frmInventory：表格
{
//声明公共变量并将用户信息输入文件流
const string FILENAME = INVENTORY.txt;
FileStream outFile = new FileStream（FILENAME，FileMode.Append，FileAccess.Write）;
public frmInventory（）
{
InitializeComponent（）;
}
private void btnAddSave_Click（对象发件人，EventArgs e）
{
//声明可变对象
字符串描述;
字符串价格;
字符串代码;
StreamWriter writer = new StreamWriter（outFile）; //打开文本文件
do
{
//输入数据
code = txtBoxCode.Text;
description = txtBoxDrscription.Text;
price = txtBoxCost.Text;
//将信息写入文本文件
writer.WriteLine（code）;
writer.WriteLine（description）;
writer.WriteLine （价格）;
txtBoxCode.Text =;
txtBoxDrscription.Text =;
txtBoxCost.Text =;
txtBoxCode.Focus（）;
}
while（rbtnLastEntry.Checked == false）;
//关闭文件
writer.Close（）;
outFile。关闭（）;
}
}
}
我试图做一个循环并添加了一个单选按钮，说明用户是否在最后一个条目中工作但仍然没有用。任何帮助，将不胜感激！ ：D
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
namespace Angie_assignment
{
public partial class frmInventory : Form
{
//declare public variables and input user info into filestream
const string FILENAME = "INVENTORY.txt";
FileStream outFile = new FileStream(FILENAME, FileMode.Append, FileAccess.Write);
public frmInventory()
{
InitializeComponent();
}
private void btnAddSave_Click(object sender, EventArgs e)
{
//declare vairables
string description;
string price;
string code;
StreamWriter writer = new StreamWriter(outFile); // open text file
do
{
//input data
code = txtBoxCode.Text;
description = txtBoxDrscription.Text;
price = txtBoxCost.Text;
//write in info to text file
writer.WriteLine(code);
writer.WriteLine(description);
writer.WriteLine(price);
txtBoxCode.Text = "";
txtBoxDrscription.Text = "";
txtBoxCost.Text = "";
txtBoxCode.Focus();
}
while (rbtnLastEntry.Checked == false);
//close file
writer.Close();
outFile.Close();
}
}
}
I tried to do a loop and added a radio button that states whether the user is at their last entry to work around but still no use. Any help would be appreciated! :D
推荐答案
假设点击触发btnAddSave_Click（顾名思义）：
- 你不需要，只需添加到文件。
- 要添加到文件而不是让它超过你需要
Assuming the btnAddSave_Click is triggered by a click (as its name implies):
- you don't need while, just add to file.
- to ADD to file instead of having it OVERWRITTEN you need
StreamWriter writer = new StreamWriter(outFile, True)如果你没有第二个参数，文件将被最后的值覆盖。
- 考虑使用指令（
if you don't have second parameter, the file will be overwritten with the last values.
- consider using directive (
using writer = new StreamWriter...{}
）用于自动关闭和处置。上面的代码有内存泄漏错误 - 如果写入文件StreamWriter有异常而File将不会关闭。
将整个内容包装成试试...最后并在finally块中关闭/处置。更好的解决方案是简单地使用using关键字。
) for automatic closure and disposal. The code above has memory leak bug - if there is an exception in writing to file StreamWriter and File will not be closed.
Wrap entire thing into Try...Finally and close / dispose in finally block. Better solution is to simply use "using" keyword.
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