一个自定义类,用于大规模的字符串连接,如拼接SQL语句。用流技术实现的,很好呦!!
using System; using System.IO; using System.Text; using System.Windows.Forms;
namespace SuperString { /// <summary> /// 创 建 者: superhood /// 内容描述: 增强字符串类 /// </summary> public class CSuperString { /// <summary> /// 功能简述: 运算符重载 /// </summary> /// <param name="Left">左参数</param> /// <param name="Right">右参数</param> /// <returns>文本类</returns> public static CSuperString operator + (string Left,CSuperString Right) { byte[] btyLeft = Encoding.Default.GetBytes(Left);//返回左参数数组 byte[] btyRight = new Byte[Right.iLength];//返回右参数数组 Right.iTextLength += Left.Length;//设置右参数文本长度 Right.iLength = btyLeft.Length + btyRight.Length;//设置右参数字节长度 Right.memStrm.Position = 0;//将右参数流位置置0 Right.memStrm.Read(btyRight,0,btyRight.Length);//将右参数数据读出
Right.memStrm.Position = 0;//将右参数流位置置0 Right.memStrm.Write(btyLeft,0,btyLeft.Length);//将字符串(字节数组)写入右参数 Right.memStrm.Write(btyRight,0,btyRight.Length);//将右参数原有信息写回(加在左参数字符串后)
return Right;//返回右参数 }
/// <summary> /// 功能简述: 运算符重载 /// </summary> /// <param name="Left">左参数</param> /// <param name="Right">右参数</param> /// <returns>文本类</returns> public static CSuperString operator + (CSuperString Left,string Right) { byte[] btyRight = Encoding.Default.GetBytes(Right);//将右参数(字符串)转换为字节数组 Left.memStrm.Position = Left.iLength;//设置左参数流的位置 Left.memStrm.Write(btyRight,0,btyRight.Length);//将右参数字符串写入流
Left.iTextLength += Right.Length;//设置左参数文本长度 Left.iLength += btyRight.Length;//设置左参数字节长度
return Left;//返回左参数 } /// <summary> /// 功能简述: 运算符重载 /// </summary> /// <param name="Left">左参数</param> /// <param name="Right">右参数</param> /// <returns>文本类</returns> public static CSuperString operator + (CSuperString Left,CSuperString Right) { byte[] btyRight = new Byte[Right.iLength];//声明字节数组(右参数) Right.memStrm.Position = 0;//将右参数流位置置0 Right.memStrm.Read(btyRight,0,btyRight.Length);//将右参数(字符串)转换为字节数组 Left.memStrm.Position = 0;//将左参数流位置置0 Left.memStrm.Write(btyRight,0,btyRight.Length);//将右参数字符串写入流 Left.iTextLength += Right.iTextLength;//设置左参数文本长度 Left.iLength += Right.iLength;//设置左参数字节长度
return Left;//返回左参数 }
/// <summary> /// 功能简述: 流中有效字节长度 /// </summary> private int iLength = 0; /// <summary> /// 功能简述: 流中文本长度 /// </summary> private int iTextLength = 0;
/// <summary> /// 功能简述: 内存流 /// </summary> private MemoryStream memStrm;
/// <summary> /// 功能简述: 构造函数 /// </summary> public CSuperString() { memStrm = new MemoryStream();//初始化流 }
/// <summary> /// 功能简述: 构造函数 /// </summary> /// <param name="DefaultLength">默认长度(以字节为单位)</param> public CSuperString(int DefaultLength) { memStrm = new MemoryStream(DefaultLength);//初始化流 }
/// <summary> /// 功能简述: 属性,字节长度 /// </summary> public int Length { get { return iLength; } }
/// <summary> /// 功能简述: 属性,文本长度 /// </summary> public int TextLength { get { return iTextLength; } }
/// <summary> /// 功能简述: 属性,流长度 /// </summary> public int Capacity { get { return memStrm.Capacity; } set { if (value >= iLength) memStrm.Capacity = value; else memStrm.Capacity = iLength; } }
/// <summary> /// 功能简述: 向类中添加字符串 /// </summary> /// <param name="Date"></param> public void AddString (string Date) { byte[] btyDate = Encoding.Default.GetBytes(Date);//字符串转换为字节数组 memStrm.Position = iLength;//设置流的位置 memStrm.Write(btyDate,0,btyDate.Length);//将字符串写入流
iTextLength += Date.Length;//设置文本长度 iLength += btyDate.Length;//设置字节长度 }
/// <summary> /// 功能简述: 返回文本 /// </summary> /// <returns>返回字符串</returns> public override string ToString() { memStrm.Position = 0;//设置流的位置 byte[] btyDate = new byte[iLength];//声明字节数组 memStrm.Read(btyDate,0,iLength);//将流内容读入数组 return Encoding.Default.GetString(btyDate);//将字节数组转换为字符串并返回 }
/// <summary> /// 功能简述: 将字符串写入文件 /// </summary> /// <param name="FileName">文件名</param> public void WriteToFile(string FileName) { FileStream strm = new FileStream(FileName,FileMode.OpenOrCreate,FileAccess.Write);//初始化文件流 //判断流长度用来确定流中是否有冗余信息 if (memStrm.Length > iLength) {//有 memStrm.Position = 0;//设置流的位置 byte[] btyDate = new byte[iLength];//声明字节数组 memStrm.Read(btyDate,0,iLength);//将流内容读入数组 strm.Write(btyDate,0,iLength);//将流内容写入文件 } else {//没有 memStrm.WriteTo(strm);//将流中文本写入文件 }
strm.Close();//关闭文件 }
/// <summary> /// 功能简述: 将字符串写入流 /// </summary> /// <param name="strm">流</param> public void WriteToStream(Stream strm) { //判断流长度用来确定流中是否有冗余信息 if (memStrm.Length > iLength) {//有 memStrm.Position = 0;//设置流的位置 byte[] btyDate = new byte[iLength];//声明字节数组 memStrm.Read(btyDate,0,iLength);//将流内容读入数组 strm.Write(btyDate,0,iLength);//将数组内容写入另一流 } else {//没有 memStrm.WriteTo(strm);//将流中文本写入另一流 } }
/// <summary> /// 功能简述: 清除流 /// </summary> public void Clear() { iLength = 0;//将流字节长度设为0 iTextLength = 0;//将流文本长度设为0 } } }

|