C#用double.TryParse()方法和NumberFormat属性设置货币金额小数点位数

目录

一、用double.TryParse()和NumberFormat属性设置

1.源码?

2.生成

二、double.TryParse()

三、CultureInfo.NumberFormat属性

1. 定义

2.实例

---

一、用double.TryParse()和NumberFormat属性设置

1.源码?

using System.Globalization;
namespace _050
{
    public partial class Form1 : Form
    {
        private GroupBox? groupBox1;
        private Button? button1;
        private ComboBox? comboBox1;
        private TextBox? textBox2;
        private TextBox? textBox1;
        private Label? label3;
        private Label? label2;
        private Label? label1;

        public Form1()
        {
            InitializeComponent();
            Load += Form1_Load;
        }
        private void Form1_Load(object? sender, EventArgs e)
        {
            // 
            // button1
            // 
            button1 = new Button
            {
                Location = new Point(138, 51),
                Name = "button1",
                Size = new Size(75, 23),
                TabIndex = 6,
                Text = "转化",
                UseVisualStyleBackColor = true
            };
            button1.Click += Button1_Click;
            // 
            // comboBox1
            //    
            comboBox1 = new ComboBox
            {
                FormattingEnabled = true,
                Location = new Point(93, 49),
                Name = "comboBox1",
                Size = new Size(39, 25),
                TabIndex = 5,
                
             };
            comboBox1.Items.AddRange([
            "1",
            "2",
            "3",
              ]);
            // 
            // textBox2
            //         
            textBox2 = new TextBox
            {
                Location = new Point(93, 80),
                Name = "textBox2",
                Size = new Size(120, 23),
                TabIndex = 4
            };
            // 
            // textBox1
            //       
            textBox1 = new TextBox
            {
                Location = new Point(93, 22),
                Name = "textBox1",
                Size = new Size(120, 23),
                TabIndex = 3
            };
            // 
            // label3
            //      
            label3 = new Label
            {
                AutoSize = true,
                Location = new Point(11, 86),
                Name = "label3",
                Size = new Size(68, 17),
                TabIndex = 2,
                Text = "转化结果："
            };
            // 
            // label2
            //            
            label2 = new Label
            {
                AutoSize = true,
                Location = new Point(11, 57),
                Name = "label2",
                Size = new Size(68, 17),
                TabIndex = 1,
                Text = "小数点位："
            };
            // 
            // label1
            //            
            label1 = new Label
            {
                AutoSize = true,
                Location = new Point(11, 28),
                Name = "label1",
                Size = new Size(68, 17),
                TabIndex = 0,
                Text = "输入金额："
            };
            // 
            // groupBox1
            // 
            groupBox1 = new GroupBox
            {
                Location = new Point(12, 12),
                Name = "groupBox1",
                Size = new Size(234, 117),
                TabIndex = 0,
                TabStop = false,
                Text = "设置小数点后位数"
            };
            groupBox1.Controls.Add(button1);
            groupBox1.Controls.Add(comboBox1);
            groupBox1.Controls.Add(textBox2);
            groupBox1.Controls.Add(textBox1);
            groupBox1.Controls.Add(label3);
            groupBox1.Controls.Add(label2);
            groupBox1.Controls.Add(label1);
            groupBox1.SuspendLayout();
            
            // 
            // Form1
            // 
            AutoScaleDimensions = new SizeF(7F, 17F);
            AutoScaleMode = AutoScaleMode.Font;
            ClientSize = new Size(258, 141);
            Controls.Add(groupBox1);
            Name = "Form1";
            StartPosition = FormStartPosition.CenterScreen;
            Text = "设置货币小数点后位数";
           
            groupBox1.ResumeLayout(false);
            groupBox1.PerformLayout();
        }

        private void Button1_Click(object? sender, EventArgs e)
        {          
            if (double.TryParse(textBox1!.Text, out double temp_value))//判断输入是否正确
            {
                NumberFormatInfo GN = //实例化NumberFormatInfo对象
                    new CultureInfo("zh-CN", false).NumberFormat;
                GN.CurrencyDecimalDigits = Convert.ToInt32(comboBox1!.Text);//设置保留位数
                textBox2!.Text = temp_value.ToString("C", GN);//将输入的小数转换为货币形式
            }
            else
            {
                MessageBox.Show("请输入正确的数值！", "提示！");//用户提示信息
            }
        }
    }
}

2.生成

?

二、double.TryParse()

? ? ? ? ?请详见本文作者写的其他文章，C#用double.TryParse(String, Double)方法将字符串类型数字转换为数值类型-CSDN博客 ?https://wenchm.blog.csdn.net/article/details/135593983

三、CultureInfo.NumberFormat属性

????????获取或设置 NumberFormatInfo，它定义适合区域性的、显示数字、货币和百分比的格式。?

1. 定义

public virtual System.Globalization.NumberFormatInfo NumberFormat { get; set; }

属性值
NumberFormatInfo
一个 NumberFormatInfo，它定义适合区域性的、显示数字、货币和百分比的格式。

例外
ArgumentNullException
该属性设置为 null。

InvalidOperationException
设置了 NumberFormat 属性或任意 NumberFormatInfo 属性，但 CultureInfo 为只读。

2.实例

// CultureInfo.NumberFormat 属性
using System.Globalization;

namespace ConsoleApp12
{
    public class SamplesCultureInfo
    {

        public static void Main()
        {

            // Creates and initializes a CultureInfo.
            CultureInfo myCI = new("en-US", false);

            // Clones myCI and modifies the DTFI and NFI instances associated with the clone.
            CultureInfo myCIclone = (CultureInfo)myCI.Clone();
            myCIclone.DateTimeFormat.AMDesignator = "a.m.";
            myCIclone.DateTimeFormat.DateSeparator = "-";
            myCIclone.NumberFormat.CurrencySymbol = "USD";
            myCIclone.NumberFormat.NumberDecimalDigits = 4;

            // Displays the properties of the DTFI and NFI instances associated with the original and with the clone.
            Console.WriteLine("DTFI/NFI PROPERTY\tORIGINAL\tMODIFIED CLONE");
            Console.WriteLine("DTFI.AMDesignator\t{0}\t\t{1}", myCI.DateTimeFormat.AMDesignator, myCIclone.DateTimeFormat.AMDesignator);
            Console.WriteLine("DTFI.DateSeparator\t{0}\t\t{1}", myCI.DateTimeFormat.DateSeparator, myCIclone.DateTimeFormat.DateSeparator);
            Console.WriteLine("NFI.CurrencySymbol\t{0}\t\t{1}", myCI.NumberFormat.CurrencySymbol, myCIclone.NumberFormat.CurrencySymbol);
            Console.WriteLine("NFI.NumberDecimalDigits\t{0}\t\t{1}", myCI.NumberFormat.NumberDecimalDigits, myCIclone.NumberFormat.NumberDecimalDigits);
        }
    }
}

/*
运行结果：
DTFI/NFI PROPERTY       ORIGINAL        MODIFIED CLONE
DTFI.AMDesignator       AM              a.m.
DTFI.DateSeparator      /               -
NFI.CurrencySymbol      $               USD
NFI.NumberDecimalDigits 3               4

*/