我正在尝试编写MS Windows计算器的副本 - 只是为了练习我在我正在做的课程中获得的知识 - 而且我在编写 Backspace 键时遇到了问题,但我不知道如何删除TxtResult.Text
(文本框)上的最后一个字符。那么,有人可以教我如何做到这一点吗?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace ZigndSuperCalc
{
public partial class FrmZigndSC : Form
{
Int64 aux, result;
Int16 cont = 0;
bool sucess;
public FrmZigndSC()
{
InitializeComponent();
}
private void BtnSoma_Click(object sender, EventArgs e)
{
sucess = Int64.TryParse(TxtInput.Text, out aux);
result += aux;
TxtInput.Text = Convert.ToString(result);
TxtInput.Focus();
}
private void BtnCE_Click(object sender, EventArgs e)
{
TxtInput.Text = "0";
}
private void BtnC_Click(object sender, EventArgs e)
{
result = 0;
TxtInput.Text = "0";
}
private void BtnBackspace_Click(object sender, EventArgs e)
{
// write here a method to delete the last character from
}
}
}
答案 0 :(得分:11)
如果我们模仿calc.exe
,那么它可能就像:
string s = TxtResult.Text;
if (s.Length > 1) {
s = s.Substring(0, s.Length - 1);
} else {
s = "0";
}
TxtResult.Text = s;
编辑:根据要求,我在这里使用的Substring
方法提取字符串的一部分并将其分配给文本框的Text
属性。请参阅:http://msdn.microsoft.com/en-us/library/aka44szs.aspx
答案 1 :(得分:4)
尝试
TxtResult.Text = TxtResult.Text.Substring(0, TxtResult.Text.Length - 1);`
答案 2 :(得分:3)
if (textBox1.TextLength > 0)
{
textBox1.Text = textBox1.Text.Substring(0, (textBox1.TextLength - 1));
}
else
{
MessageBox.Show("No Number.");
}
答案 3 :(得分:2)
我使用这种方法:
private void button_Click(object sender, EventArgs e)
{
if (textbox.Text.Length > 0)
{
textbox.Text = textbox.Text.Remove(textbox.Text.Length - 1);
}
}
答案 4 :(得分:0)
//CLICK ON BUTTON1
private void button1_Click(object sender, EventArgs e)
{
if (textBox1.Text.Length > 1)
{
textBox1.Text = textBox1.Text.Substring(0, textBox1.Text.Length - 1);
}![enter image description here][1]
else
{
textBox1.Text = "0";
}
}
答案 5 :(得分:0)
You have to create a Button named "buttonDel" then
private void buttonDel_Click(object sender, EventArgs e)
{
if (sender == buttonDel)
{
s = textBox1.Text;
if (s.Length > 1)
{
s = s.Substring(0,s.Length - 1);
textBox1.Text = s;
}
else
{
textBox1.Text = "0";
}
}
}
答案 6 :(得分:0)
这对我有用!!
private void txtNumCL_TextChanged(object sender, EventArgs e)
{
bool ctrl = Int32.TryParse(txtNumCL.Text, out int outParse);
if (!ctrl && txtNumCL.Text.Length > 0)
{
txtNumCL.Text = txtNumCL.Text.Substring(0, txtNumCL.Text.Length - 1);
txtNumCL.SelectionStart = txtNumCL.Text.Length;
}
}
答案 7 :(得分:0)
已更新:
output.Text=output.Text.Remove(output.Text.Length-1, 1);
旧: 您可以使用:
TxtInput.Text = TxtInput.Text.ToString().Remove(TxtInput.Text.ToString().Length-1,1);