common.cs

某个公司需要维持良好的客户关系

using System;
using System.Data;
using System.Collections;
using System.Security.Cryptography;
using System.Text;
using System.Text.RegularExpressions;
using CRM.Model;
using CRM.IDAL;

namespace CRM.BLL
{
	/// <summary>
	/// 通用的方法类.包含通用的方法.
	/// </summary>
	public  class Common
	{
		#region 过滤字符串
		/// <summary>
		/// 过滤字符串
		/// </summary>
		/// <param name="inputString">字符串</param>
		/// <param name="maxLength">截取长度</param>
		/// <returns></returns>
		public  static  string CleanString(string inputString, int maxLength) 
		{

			
			StringBuilder retVal = new StringBuilder();

			// check incoming parameters for null or blank string
			if ((inputString != null) && (inputString != String.Empty)) 
			{
				inputString = inputString.Trim();

				//chop the string incase the client-side max length
				//fields are bypassed to prevent buffer over-runs
				if (inputString.Length > maxLength)
					inputString = inputString.Substring(0, maxLength);

				//convert some harmful symbols incase the regular
				//expression validators are changed
				for (int i = 0; i < inputString.Length; i++) 
				{
					switch (inputString[i]) 
					{
						case '"':
							retVal.Append("&quot;");
							break;
						case '<':
							retVal.Append("&lt;");
							break;
						case '>':
							retVal.Append("&gt;");
							break;
						default:
							retVal.Append(inputString[i]);
							break;
					}
				}

				// Replace single quotes with white space
				retVal.Replace("'", " ");
			}

			return retVal.ToString();
			
		}
		#endregion

		#region 检测字符串是否为空
		/// <summary>
		/// 检测字符串是否为空
		/// </summary>
		/// <param name="str"></param>
		/// <returns></returns>
		public static   bool CheckStrIsNull(params string[] str)
		{
			foreach(string s in str)
				if(s ==null||s.Trim() == string.Empty)
					return true;
			return false;
			
		}
		#endregion 

		#region 加解密字符串
		/// <summary>
		/// 加解密字符串
		/// </summary>
		/// <param name="String">字符串</param>
		/// <returns></returns>
		public  static  string Encrypt(string str)
		{
			Byte[] clearBytes = new UnicodeEncoding().GetBytes(str);
			Byte[] hashedBytes = ((HashAlgorithm) CryptoConfig.CreateFromName("MD5")).ComputeHash(clearBytes);
			
			return BitConverter.ToString(hashedBytes);
		}
		#endregion
	}
}