C#判断输入的数字是否符合货币格式

目录

一、用正则表达式判断输入是否符合货币格式

二、用double.TryParse()判断输入是否符合货币格式

---

一、用正则表达式判断输入是否符合货币格式

// 判断输入是否货币合格
using System.Text.RegularExpressions;
namespace IsCurrency_Format
{
    partial class Program
    {
        static void Main(string[] args)
        {
            ArgumentNullException.ThrowIfNull(args);

            Console.WriteLine("请输入要判断的字符串（货币格式）");
            string input = Console.ReadLine()!.ToString();

            bool isValidFormat = IsCurrencyFormat(input);

            if (isValidFormat)
            {
                Console.WriteLine("该字符串是有效的货币格式！");
            }
            else
            {
                Console.WriteLine("该字符串不是有效的货币格式！");
            }    
            Console.ReadKey();// 等待按任意键结束程序
        }

        static bool IsCurrencyFormat(string input)
        {
            Regex regex = MyRegex();
            return regex.IsMatch(input);
        }

        [GeneratedRegex(@"^[+-]?\d+(,\d{3})*(\.\d{1,2})?$")]
        private static partial Regex MyRegex();
    }
}
//运行结果：
/*
请输入要判断的字符串（货币格式）
88888.88
该字符串是有效的货币格式！
 */

二、用double.TryParse()判断输入是否符合货币格式

//判断输入是否符合货币格式
using System.Globalization;
namespace _051
{
    public partial class Form1 : Form
    {
        private GroupBox? groupBox1;
        private Button? button1;
        private TextBox? textBox2;
        private TextBox? textBox1;
        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(209, 65),
                Name = "button1",
                Size = new Size(75, 23),
                TabIndex = 4,
                Text = "判断",
                UseVisualStyleBackColor = true
            };
            button1.Click += Button1_Click;
            // 
            // textBox2
            // 
            textBox2 = new TextBox
            {
                Location = new Point(77, 65),
                Name = "textBox2",
                Size = new Size(126, 23),
                TabIndex = 3
            };
            // 
            // textBox1
            //      
            textBox1 = new TextBox
            {
                Location = new Point(77, 27),
                Name = "textBox1",
                Size = new Size(126, 23),
                TabIndex = 2
            };
            // 
            // label2
            //          
            label2 = new Label
            {
                AutoSize = true,
                Location = new Point(6, 71),
                Name = "label2",
                Size = new Size(68, 17),
                TabIndex = 1,
                Text = "转换结果："
            };
            // 
            // label1
            //            
            label1 = new Label
            {
                AutoSize = true,
                Location = new Point(6, 30),
                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(290, 117),
                TabIndex = 0,
                TabStop = false,
                Text = "是否符合货币格式"
            };
            groupBox1.Controls.Add(button1);
            groupBox1.Controls.Add(textBox2);
            groupBox1.Controls.Add(textBox1);
            groupBox1.Controls.Add(label2);
            groupBox1.Controls.Add(label1);
            groupBox1.SuspendLayout();
            
            // 
            // Form1
            // 
            AutoScaleDimensions = new SizeF(7F, 17F);
            AutoScaleMode = AutoScaleMode.Font;
            ClientSize = new Size(314, 141);
            Controls.Add(groupBox1);
            Name = "Form1";
            StartPosition = FormStartPosition.CenterScreen;
            Text = "判断是否符合货币格式";
            groupBox1.ResumeLayout(false);
            groupBox1.PerformLayout();
        }

        private void Button1_Click(object? sender, EventArgs e)
        {
            if (double.TryParse(textBox1!.Text, out double temp))   //验证输入是否正确并赋值
            {
                NumberFormatInfo GN =new CultureInfo("zh-CN", false).NumberFormat;//实例化NumberFormatInfo对象
                GN.CurrencyGroupSeparator = ",";        //设置货币值中用来分组的字符串
                textBox2!.Text = temp.ToString("C", GN);//格式化为货币格式并显示
            }
            else
            {
                MessageBox.Show("请输入正确的货币值！", "提示！");
            }
        }
    }
}