类库------对一些字符串进行操作的类1.判断输入是否数字2.截取字符串函数3.过滤输入信息4.生成随机数5.生成验证码图片6.获取汉字第一个拼音7.半角转全角8.全角转半角

using System;
using System.Drawing;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Text.RegularExpressions;
using System.IO;
using System.Drawing.Imaging;
using System.Text;
using System.Web.Security;

namespace WeYyzyq.Comp
...{
    /**//// <summary>
    /// 对一些字符串进行操作的类
    /// 创建时间：2006-8-3
    /// 创建者：马先光
    /// </summary>
    public class StringUtil
    ...{
        private static string passWord;    //加密字符串

        /**//// <summary>
        /// 判断输入是否数字
        /// </summary>
        /// <param name="num">要判断的字符串</param>
        /// <returns></returns>
        static public bool VldInt(string num)
        ...{
            ...#region
            try
            ...{
                Convert.ToInt32(num);
                return true;
            }
            catch ...{ return false; }
            #endregion
        }

        /**//// <summary>
        /// 返回文本编辑器替换后的字符串
        /// </summary>
        /// <param name="str">要替换的字符串</param>
        /// <returns></returns>
        static public string GetHtmlEditReplace(string str)
        ...{
            ...#region
            return str.Replace("'", "''").Replace("&nbsp;", " ").Replace(",", "，").Replace("%", "％").Replace("script","").Replace(".js","");
            #endregion
        }

        /**//// <summary>
        /// 截取字符串函数
        /// </summary>
        /// <param name="str">所要截取的字符串</param>
        /// <param name="num">截取字符串的长度</param>
        /// <returns></returns>
        static public string GetSubString(string str, int num)
        ...{
            ...#region
            return (str.Length > num) ? str.Substring(0, num) + "..." : str;
            #endregion
        }

        /**//// <summary>
        /// 过滤输入信息
        /// </summary>
        /// <param name="text">内容</param>
        /// <param name="maxLength">最大长度</param>
        /// <returns></returns>
        public static string InputText(string text, int maxLength)
        ...{
            ...#region
            text = text.Trim();
            if (string.IsNullOrEmpty(text))
                return string.Empty;
            if (text.Length > maxLength)
                text = text.Substring(0, maxLength);
            text = Regex.Replace(text, "[/s]{2,}", " ");    //two or more spaces
            text = Regex.Replace(text, "(<[b|B][r|R]/*>)+|(<[p|P](.|/n)*?>)", " ");    //<br><p>
            text = Regex.Replace(text, "(/s*&[n|N][b|B][s|S][p|P];/s*)+", " ");    //&nbsp;
            text = Regex.Replace(text, "<(.|/n)*?>", string.Empty);    //any other tags
            text = text.Replace("'", "''");
            return text;
            #endregion
        }

        /**//// <summary>
        /// 生成随机数
        /// </summary>
        /// <returns></returns>
        private string GenerateCheckCode()
        ...{
            ...#region
            int number;
            char code;
            string checkCode = String.Empty;

            System.Random random = new Random();

            for (int i = 0; i < 5; i++)
            ...{
                number = random.Next();

                if (number % 2 == 0)
                    code = (char)('0' + (char)(number % 10));
                else
                    code = (char)('A' + (char)(number % 26));

                checkCode += code.ToString();
            }

            HttpContext.Current.Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));

            return checkCode;
            #endregion
        }


        /**//// <summary>
        /// 生成验证码图片
        /// </summary>
        public void CreateCheckCodeImage()
        ...{
            ...#region
            string checkCode = GenerateCheckCode();
            if (checkCode == null || checkCode.Trim() == String.Empty)
                return;

            System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
            Graphics g = Graphics.FromImage(image);

            try
            ...{
                //生成随机生成器
                Random random = new Random();

                //清空图片背景色
                g.Clear(Color.White);

                //画图片的背景噪音线
                for (int i = 0; i < 25; i++)
                ...{
                    int x1 = random.Next(image.Width);
                    int x2 = random.Next(image.Width);
                    int y1 = random.Next(image.Height);
                    int y2 = random.Next(image.Height);

                    g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
                }

                Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
                System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
                g.DrawString(checkCode, font, brush, 2, 2);

                //画图片的前景噪音点
                for (int i = 0; i < 100; i++)
                ...{
                    int x = random.Next(image.Width);
                    int y = random.Next(image.Height);

                    image.SetPixel(x, y, Color.FromArgb(random.Next()));
                }

                //画图片的边框线
                g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);

                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
                HttpContext.Current.Response.ClearContent();
                HttpContext.Current.Response.ContentType = "image/Gif";
                HttpContext.Current.Response.BinaryWrite(ms.ToArray());
            }
            finally
            ...{
                g.Dispose();
                image.Dispose();
            }
            #endregion
        }


        /**//// <summary>
        /// 获取汉字第一个拼音
        /// </summary>
        /// <param name="input"></param>
        /// <returns></returns>
        static public string getSpells(string input)
        ...{
            ...#region
            int len = input.Length;
            string reVal = "";
            for (int i = 0; i < len; i++)
            ...{
                reVal += getSpell(input.Substring(i, 1));
            }
            return reVal;
            #endregion
        }

        static public string getSpell(string cn)
        ...{
            ...#region
            byte[] arrCN = Encoding.Default.GetBytes(cn);
            if (arrCN.Length > 1)
            ...{
                int area = (short)arrCN[0];
                int pos = (short)arrCN[1];
                int code = (area << 8) + pos;
                int[] areacode = ...{ 45217, 45253, 45761, 46318, 46826, 47010, 47297, 47614, 48119, 48119, 49062, 49324, 49896, 50371, 50614, 50622, 50906, 51387, 51446, 52218, 52698, 52698, 52698, 52980, 53689, 54481 };
                for (int i = 0; i < 26; i++)
                ...{
                    int max = 55290;
                    if (i != 25) max = areacode[i + 1];
                    if (areacode[i] <= code && code < max)
                    ...{
                        return Encoding.Default.GetString(new byte[] ...{ (byte)(65 + i) });
                    }
                }
                return "?";
            }
            else return cn;
            #endregion
        }


        /**//// <summary>
        /// 半角转全角
        /// </summary>
        /// <param name="BJstr"></param>
        /// <returns></returns>
        static public string GetQuanJiao(string BJstr)
        ...{
            ...#region
            char[] c = BJstr.ToCharArray();
            for (int i = 0; i < c.Length; i++)
            ...{
                byte[] b = System.Text.Encoding.Unicode.GetBytes(c, i, 1);
                if (b.Length == 2)
                ...{
                    if (b[1] == 0)
                    ...{
                        b[0] = (byte)(b[0] - 32);
                        b[1] = 255;
                        c[i] = System.Text.Encoding.Unicode.GetChars(b)[0];
                    }
                }
            }

            string strNew = new string(c);
            return strNew;

            #endregion
        }

        /**//// <summary>
        /// 全角转半角
        /// </summary>
        /// <param name="QJstr"></param>
        /// <returns></returns>
        static public string GetBanJiao(string QJstr)
        ...{
            ...#region
            char[] c = QJstr.ToCharArray();
            for (int i = 0; i < c.Length; i++)
            ...{
                byte[] b = System.Text.Encoding.Unicode.GetBytes(c, i, 1);
                if (b.Length == 2)
                ...{
                    if (b[1] == 255)
                    ...{
                        b[0] = (byte)(b[0] + 32);
                        b[1] = 0;
                        c[i] = System.Text.Encoding.Unicode.GetChars(b)[0];
                    }
                }
            }
            string strNew = new string(c);
            return strNew;
            #endregion
        }

        加密的类型#region 加密的类型
        /**//// <summary>
        /// 加密的类型
        /// </summary>
        public enum PasswordType
        ...{
            SHA1,
            MD5
        }
        #endregion


        /**//// <summary>
        /// 字符串加密
        /// </summary>
        /// <param name="PasswordString">要加密的字符串</param>
        /// <param name="PasswordFormat">要加密的类别</param>
        /// <returns></returns>
        static public string EncryptPassword(string PasswordString, string PasswordFormat)
        ...{
            ...#region
            switch (PasswordFormat)
            ...{
                case "SHA1":
                    ...{
                        passWord = FormsAuthentication.HashPasswordForStoringInConfigFile(PasswordString, "SHA1");
                        break;
                    }
                case "MD5":
                    ...{
                        passWord = FormsAuthentication.HashPasswordForStoringInConfigFile(PasswordString, "MD5");
                        break;
                    }
                default:
                    ...{
                        passWord = string.Empty;
                        break;
                    }
            }
            return passWord;
            #endregion
        }
        
    }
}