在我们写程序的时候,特别是数据库应用程序的时候,经常会遇到这样的情况:对于一个给定的表,写出这个表对应的类(用一句时髦的话说是实现业务实体类),类的数据成员是所有的字段,并且类含有该表的添加修改删除等操作。还有,对于一个给定的存储过程,要完成根据存储过程存取数据或别的数据库操作。如下代码就是我们通常要完成的:
1.表的业务实体化
private int iId ;
public int Id
{
get
{
return iId ;
}
set
{
iId = value ;
}
}
private string strName ;
public string Name
{
get
{
return strName ;
}
set
{
strName = value ;
}
}
private string strCode ;
public string Code
{
get
{
return strCode ;
}
set
{
strCode = value ;
}
}
private string strDescription ;
public string Description
{
get
{
return strDescription ;
}
set
{
strDescription = value ;
}
}
private int iFatherid ;
public int Fatherid
{
get
{
return iFatherid ;
}
set
{
iFatherid = value ;
}
}
private int iType ;
public int Type
{
get
{
return iType ;
}
set
{
iType = value ;
}
}
private int iUserId ;
public int UserId
{
get
{
return iUserId ;
}
set
{
iUserId = value ;
}
}
ublic bool Add()
{
SqlConnection conn = SqlConn.Instance().Connection ;
string strSql = "insert into book(id, Name, Code, Description, Fatherid, Type, UserId)"
+"values(@id, @Name, @Code, @Description, @Fatherid, @Type, @UserId)" ;
SqlCommand command = new SqlCommand(strSql,conn) ;
command.Parameters.Add("@id",SqlDbType.Int ) ;
command.Parameters["@id"].value = iId ;
command.Parameters.Add("@Name",SqlDbType.NVarChar ,50) ;
if (strName!= null )
command.Parameters["@Name"].value = strName ;
else
command.Parameters["@Name"].value = DBNull.value ;
command.Parameters.Add("@Code",SqlDbType.NVarChar ,255) ;
if (strCode!= null )
command.Parameters["@Code"].value = strCode ;
else
command.Parameters["@Code"].value = DBNull.value ;
command.Parameters.Add("@Description",SqlDbType.NVarChar ,255) ;
if (strDescription!= null )
command.Parameters["@Description"].value = strDescription ;
else
command.Parameters["@Description"].value = DBNull.value ;
command.Parameters.Add("@Fatherid",SqlDbType.Int ) ;
command.Parameters["@Fatherid"].value = iFatherid ;
command.Parameters.Add("@Type",SqlDbType.Int ) ;
command.Parameters["@Type"].value = iType ;
command.Parameters.Add("@UserId",SqlDbType.Int ) ;
command.Parameters["@UserId"].value = iUserId ;
try
{
conn.Open() ;
command.ExecuteNonQuery() ;
return true ;
}
catch(Exception e)
{
throw(new Exception("Error in the Database"+e.Message)) ;
}
finally
{
conn.Close() ;
}
}
public bool Modify()
{
SqlConnection conn = SqlConn.Instance().Connection ;
string strSql ="update book set id = @id, Name = @Name, Code = @Code, Description = @Description, Fatherid = @Fatherid, Type = @Type, UserId = @UserId "
+ " where id =@id " ;
SqlCommand command = new SqlCommand(strSql,conn) ;
command.Parameters.Add("@id",SqlDbType.Int ) ;
command.Parameters["@id"].value = iId ;
command.Parameters.Add("@Name",SqlDbType.NVarChar ,50) ;
command.Parameters["@Name"].value = strName ;
command.Parameters.Add("@Code",SqlDbType.NVarChar ,255) ;
command.Parameters["@Code"].value = strCode ;
command.Parameters.Add("@Description",SqlDbType.NVarChar ,255) ;
command.Parameters["@Description"].value = strDescription ;
command.Parameters.Add("@Fatherid",SqlDbType.Int ) ;
command.Parameters["@Fatherid"].value = iFatherid ;
command.Parameters.Add("@Type",SqlDbType.Int ) ;
command.Parameters["@Type"].value = iType ;
command.Parameters.Add("@UserId",SqlDbType.Int ) ;
command.Parameters["@UserId"].value = iUserId ;
try
{
conn.Open() ;
command.ExecuteNonQuery() ;
return true ;
}
catch(Exception e)
{
throw(new Exception("Error in the Database"+e.Message)) ;
}
finally
{
conn.Close() ;
}
}
再看一下存储过程:
public bool ExeSP_ddms_Modify_Trx(
int aiPrsn_trx_no,
int aiUlt_incid_no,
int aiPrsn_trx_status_cd,
DateTime adtTrx_cmpl_dt,
string astrEmail_addr)
{
SqlConnection conn = SqlConn.Instance().Connection ;
string strSPName = "ddms_Modify_Trx" ;
SqlCommand command = new SqlCommand(strSPName,conn) ;
command.CommandType = CommandType.StoredProcedure ;
command.Parameters.Add("@prsn_trx_no",SqlDbType.SmallInt ) ;
command.Parameters["@prsn_trx_no"].value= aiPrsn_trx_no ;
command.Parameters.Add("@ult_incid_no",SqlDbType.Int ) ;
command.Parameters["@ult_incid_no"].value= aiUlt_incid_no ;
command.Parameters.Add("@prsn_trx_status_cd",SqlDbType.Int ) ;
command.Parameters["@prsn_trx_status_cd"].value= aiPrsn_trx_status_cd ;
command.Parameters.Add("@trx_cmpl_dt",SqlDbType.DateTime ) ;
if ( adtTrx_cmpl_dt!= DateTime.Minvalue )
command.Parameters["@trx_cmpl_dt"].value= adtTrx_cmpl_dt ;
else
command.Parameters["@trx_cmpl_dt"].value= DBNull.value ;
command.Parameters.Add("@email_addr",SqlDbType.VarChar ,70) ;
if ( astrEmail_addr!= null )
command.Parameters["@email_addr"].value= astrEmail_addr ;
else
command.Parameters["@email_addr"].value= DBNull.value ;
try
{
conn.Open() ;
command.ExecuteNonQuery() ;
return true ;
}
catch(Exception e)
{
throw(new Exception("Error in the Database"+e.Message)) ;
}
finally
{
conn.Close() ;
}
}
上面处理表的代码也挺长的,但那只是7个字段,如果一个表含有二三十个字段的话,恐怕代码更长,同样,检查你写好的代码是否有错误也是一个痛苦的过程。
但是,写这些代码本身并没有多少难度,而且很多工作都是重复的,这就不能不启发我们通过一个程序来完成这些繁琐易出错的工作。
假如让我们来设计一个程序完成上面的代码,我们应该怎么做哪?
要完成上面的工作,我们首先应该找到我们要处理的表或存储过程。
我们也可以通过编程实现:
1.列出所有的数据库服务器
public static ArrayList GetServerList()
{
ArrayList alServers = new ArrayList() ;
SQLDMO.Application sqlApp = new SQLDMO.ApplicationClass() ;
try
{
SQLDMO.NameList serverList = sqlApp.ListAvailableSQLServers() ;
for(int i = 1;i<= serverList.Count;i++)
{
alServers.Add(serverList.Item(i)) ;
}
}
catch(Exception e)
{
throw(new Exception("取数据库服务器列表出错:"+e.Message)) ;
}
finally
{
sqlApp.Quit() ;
}
return alServers ;
}
这样,所有的数据库服务器迷宫凝成都存在了ArrayList里,我们可以用一个下拉列表来列出所有的服务器,让用户选择他需要的一个。
2。得到选定服务器所有的数据库列表
要完成这个工作,我们需要用户输入这个数据库服务器的用户名和密码,代码如下:
public static ArrayList GetDbList(string strServerName,string strUserName,string strPwd)
{
ArrayList alDbs = new ArrayList() ;
SQLDMO.Application sqlApp = new SQLDMO.ApplicationClass() ;
SQLDMO.SQLServer svr = new SQLDMO.SQLServerClass() ;
try
{
svr.Connect(strServerName,strUserName,strPwd) ;
foreach(SQLDMO.Database db in svr.Databases)
{
if(db.Name!=null)
alDbs.Add(db.Name) ;
}
}
catch(Exception e)
{
throw(new Exception("连接数据库出错:"+e.Message)) ;
}
finally
{
svr.DisConnect() ;
sqlApp.Quit() ;
}
return alDbs ;
}
这样就得到了数据库的列表,你同样可以让用户选择一个数据库。
3。列出选定数据库所有的用户表和存储过程
在这一步我们不用SQLDMO了,我们通过读取选定数据库的sysobjects表中的记录实现,当然,完成这个工作需要如下信息:你选择的数据库服务器名,用户名,密码,数据库名等信息:
public static ArrayList GetTableList(string strServerName,string strDBName,string strUserName,string strPwd)
{
string strConStr = " data source="+ strServerName +";initial catalog="+strDBName +
";password="+ strPwd+";persist security info=True;user id="+ strUserName;
SqlConnection conn = new SqlConnection(strConStr) ;
ArrayList alTbs = new ArrayList() ;
string strSql = "select * from sysobjects where (xtype='u' or xtype='p') and category<>2 order by name" ;
SqlCommand comm = new SqlCommand(strSql,conn) ;
SqlDataReader sr = null ;
try
{
conn.Open() ;
sr = comm.ExecuteReader() ;
while(sr.Read())
{
string strName = sr["name"].ToString() ;
bool blTable = sr["xtype"].ToString().Trim().ToUpper() == "U"?true:false ;
TableInfo tb = new TableInfo(strName,blTable) ;
alTbs.Add(tb) ;
}
}
catch(Exception err)
{
throw(new Exception("取表明列表出错:"+err.Message)) ;
}
finally
{
if (sr != null)
{
sr.Close() ;
sr = null ;
}
conn.Close() ;
}
return alTbs ;
}
这样我们就得到了所有的用户表和存储过程,注意这一句:
select * from sysobjects where (xtype='u' or xtype='p') and category<>2 order by name,这是关键的sql语句,其中xtype='u' 表示用户表,xtype='p'表示存储过程,category<>2表示不是系统存储过程。
下一步是取得选定表的所有字段或存储过程的所有参数
我们从表syscolumns取得我们想要到的东西:
strTableName = tbInfo.Name ;
string strSql = "select * from syscolumns where id=( " +
" select id from sysobjects where name='"+ strTableName + "')" ;
SqlDataAdapter sa = new SqlDataAdapter(strSql,conn) ;
DataSet ds = new DataSet() ;
sa.Fill(ds) ;
这样我们就把某个表(或存储过程)的所有字段信息放到了结果集ds里。
在syscolumns 里有一个字段xtype,该字段表示列的数据类型,俺定义了两个函数,能根据xtype的值得到对应的dotnet中的数据类型和sqldb数据类型:
private string getType(int iType)
{
string strResult = "" ;
switch(iType)
{
case 34:
strResult = "Byte[]" ;
break ;
case 35:
case 99:
case 167:
case 175:
case 231:
case 239:
strResult = "string" ;
break ;
case 48:
case 52:
case 56:
case 127:
strResult = "int" ;
break ;
case 58:
case 61:
strResult = "DateTime" ;
break ;
case 59:
strResult = "Single" ;
break ;
case 60:
case 106:
case 108:
case 122:
strResult = "Decimal" ;
break ;
case 62:
strResult = "Double" ;
break ;
case 104:
strResult = "bool" ;
break ;
default:
strResult = "None" ;//"unknow" ;
break ;
}
return strResult + " " ;
}
private string getSqlDBType(int iType)
{
string strResult = "" ;
switch(iType)
{
case 34:
strResult = "SqlDbType.Image" ;
break ;
case 35:
strResult = "SqlDbType.Text" ;
break ;
case 48:
strResult = "SqlDbType.TinyInt" ;
break ;
case 52:
strResult = "SqlDbType.SmallInt" ;
break ;
case 56:
strResult = "SqlDbType.Int" ;
break ;
case 58:
strResult = "SqlDbType.SmallDateTime" ;
break ;
case 59:
strResult = "SqlDbType.Real" ;
break ;
case 60:
strResult = "SqlDbType.Money" ;
break ;
case 61:
strResult = "SqlDbType.DateTime" ;
break ;
case 62:
strResult = "SqlDbType.Float" ;
break ;
case 99:
strResult = "SqlDbType.NText" ;
break ;
case 104:
strResult = "SqlDbType.Bit" ;
break ;
case 106:
strResult = "SqlDbType.Decimal" ;
break ;
case 108:
strResult = "SqlDbType.Decimal" ;
break ;
case 122:
strResult = "SqlDbType.SmallMoney" ;
break ;
case 127:
strResult = "SqlDbType.BigInt" ;
break ;
case 165:
strResult = "SqlDbType.VarBinary" ;
break ;
case 167:
strResult = "SqlDbType.VarChar" ;
break ;
case 173:
strResult = "SqlDbType.Binary" ;
break ;
case 175:
strResult = "SqlDbType.Char" ;
break ;
case 189:
strResult = "SqlDbType.Timestamp" ;
break ;
case 231:
strResult = "SqlDbType.NVarChar" ;
break ;
case 239:
strResult = "SqlDbType.NChar" ;
break ;
default:
strResult = "None" ;//"unknow" ;
break ;
}
return strResult + " " ;
}
当然,还有一个函数先介绍一下,后面有它的具体用法:
private string getTypeShort(int iType)
{
string strResult = "" ;
switch(getType(iType).Trim())
{
case "Byte[]":
strResult = "img" ;
break ;
case "string":
strResult = "str" ;
break ;
case "int":
strResult = "i" ;
break ;
case "DateTime":
strResult = "dt" ;
break ;
case "Single":
strResult = "sig" ;
break ;
case "Decimal":
strResult = "dec" ;
break ;
case "Double":
strResult = "db" ;
break ;
case "bool":
strResult = "bl" ;
break ;
default:
strResult = "unknow" ;
break ;
}
return strResult ;
}
现在有了上面的介绍和函数基础,我们可以逐步实现我们的目标了:
1.生成数据实体类的数据成员
大家看一下,对于一个字段id,整形,我们这样定义:
private int iId ;
public int Id
{
get
{
return iId ;
}
set
{
iId = value ;
}
}
其中iId表示数据类型+字段名称,其中字段名称的第一个字母大写,代码实现如下:
private string BuildMember(DataSet ds)
{
StringBuilder sb = new StringBuilder() ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
int iType = (byte)dr["xtype"] ;
string strType = getType(iType) ;
string strName = dr["name"].ToString() ;
strName = UpFirstChar(strName) ;
string strShortType = getTypeShort(iType) ;
string strPrivateline = "private " + strType + strShortType +strName +" ;\r\n" ;
sb.Append(strPrivateline) ;
string strPublicline = "public " + strType + strName +" \r\n" ;
sb.Append(strPublicline) ;
sb.Append("{\r\n") ;
sb.Append("\tget\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\treturn " +strShortType +strName+ " ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\tset\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\t" +strShortType +strName+ " = value ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("}\r\n") ;
sb.Append("\r\n") ;
sb.Append("\r\n") ;
}
return sb.ToString();
}
参数DataSet ds中的ds是通过上一页的sa.Fill(ds)得到的,dr["name"]表示字段名称,dr["xtype"] 是字段类型。
UpFirstChar函数负责把字符串的第一个字母大写:
private string UpFirstChar(string strvalue)
{
return strvalue.Substring(0,1).ToUpper() + strvalue.Substring(1,strvalue.Length - 1) ;
}
这样就生成了数据实体的数据成员。
2。生成Add方法
Add方法生成起来有点难度,可以参考第一页的程序,我们这里是通过参数的方法来实现add的。有一点要注意,就是在对参数赋值时要考虑参数值为空的情况。代码实现如下:
private string BuildAddFunction(DataSet ds)
{
StringBuilder sb = new StringBuilder() ;
sb.Append("public bool Add()\r\n") ;
sb.Append("{\r\n") ;
sb.Append("\tSqlConnection conn = SqlConn.Instance().Connection ;\r\n") ;
sb.Append("\r\n") ;
string strInsert = "\"insert into " + strTableName + "(";
string strFiledList = "" ;
string strParamList = "" ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
string strName = dr["name"].ToString() ;
strFiledList = strFiledList + strName + ", " ;
strParamList = strParamList + "@" + strName + ", " ;
}
strFiledList = strFiledList.Trim().TrimEnd(',') ;
strParamList = strParamList.Trim().TrimEnd(',') ;
sb.Append("\tstring strSql = " + strInsert + strFiledList+ ")\"\r\n") ;
sb.Append("\t+\"values(" + strParamList+ ")\" ;\r\n") ;
sb.Append("\r\n") ;
sb.Append("\tSqlCommand command = new SqlCommand(strSql,conn) ;\r\n") ;
sb.Append("\r\n") ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
string strName = dr["name"].ToString() ;
string strSqlType = getSqlDBType((byte)dr["xtype"]) ;
string strShortType = getTypeShort((byte)dr["xtype"]) ;
string strvalueName = strShortType + UpFirstChar(strName) ;
int iLen = (Int16)dr["prec"] ;
string strLen = "" ;
if (strShortType == "str")
strLen = strLen + "," + iLen ;
string strCommandName = "\tcommand.Parameters.Add(\"@" + strName + "\"," + strSqlType + strLen+ ") ;\r\n" ;
string strCommandvalue = "\tcommand.Parameters[\"@" + strName + "\"].value = " + strvalueName + " ;\r\n" ;
string strCommandNullvalue = "\tcommand.Parameters[\"@" + strName + "\"].value = DBNull.value ;\r\n" ;
sb.Append(strCommandName) ;
if (strShortType == "dt")
sb.Append("\tif (" + strvalueName + "!= DateTime.Minvalue )\r\n") ;
else if (strShortType == "str")
sb.Append("\tif (" + strvalueName + "!= null )\r\n") ;
else if (strShortType == "img")
sb.Append("\tif (" + strvalueName + "!= null )\r\n") ;
else
sb.Append("") ;
sb.Append(strCommandvalue) ;
if (strShortType == "dt" ||strShortType == "str"||strShortType == "img")
{
sb.Append("\telse\r\n") ;
sb.Append(strCommandNullvalue) ;
}
sb.Append("\r\n") ;
}
sb.Append(AddCatchString()) ;
sb.Append("}\r\n") ;
return sb.ToString();
}
3。edit,delete的实现方法类似与add,就不详细说了,edit方法代码如下:
private string BuildModifyFunction(DataSet ds)
{
StringBuilder sb = new StringBuilder() ;
sb.Append("public bool Modify()\r\n") ;
sb.Append("{\r\n") ;
sb.Append("\tSqlConnection conn = SqlConn.Instance().Connection ;\r\n") ;
string strModify = "string strSql =\"update " + strTableName + " set ";
string strParamList = "" ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
string strName = dr["name"].ToString() ;
strParamList = strParamList + strName + " = @" + strName + ", " ;
}
strParamList = strParamList.Trim().TrimEnd(',') ;
sb.Append("\t" + strModify + strParamList + " \"\r\n") ;
sb.Append("\t+ \" where id =@id \" ;\r\n") ;
sb.Append("\tSqlCommand command = new SqlCommand(strSql,conn) ;\r\n") ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
string strName = dr["name"].ToString() ;
string strSqlType = getSqlDBType((byte)dr["xtype"]) ;
string strShortType = getTypeShort((byte)dr["xtype"]) ;
string strvalueName = strShortType + UpFirstChar(strName) ;
int iLen = (Int16)dr["prec"] ;
string strLen = "" ;
if (strShortType == "str")
strLen = strLen + "," + iLen ;
string strCommandName = "\tcommand.Parameters.Add(\"@" + strName + "\"," + strSqlType + strLen + ") ;\r\n" ;
string strCommandvalue = "\tcommand.Parameters[\"@" + strName + "\"].value = " + strvalueName + " ;\r\n" ;
sb.Append(strCommandName) ;
sb.Append(strCommandvalue) ;
sb.Append("\r\n") ;
}
sb.Append(AddCatchString()) ;
sb.Append("}\r\n") ;
return sb.ToString();
}
4。生成存储过程的执行方法和返回结果方法。存储过程的参数也在syscolumns表里有详细的说明,里面还记录了每个参数是不是传出参数,不过在这个函数里我没有考虑参数的方向,当然,要考虑进去也不是很麻烦。
private string BuildSPExec(DataSet ds)
{
StringBuilder sb = new StringBuilder() ;
string strFuncParam = "" ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
int iType = (byte)dr["xtype"] ;
string strName = UpFirstChar(dr["name"].ToString().TrimStart('@')) ;
string strType = getType(iType) ;
string strSqlType = getSqlDBType(iType) ;
string strShortType = getTypeShort(iType) ;
strFuncParam = strFuncParam + "\r\n\t\t" + strType + " a" + strShortType + strName + ",";
}
strFuncParam = strFuncParam.TrimEnd(',') ;
string strDef = "public bool ExeSP_" + strTableName + "(" + strFuncParam + ")\r\n";
sb.Append(strDef) ;
sb.Append("{\r\n") ;
sb.Append("\tSqlConnection conn = SqlConn.Instance().Connection ;\r\n") ;
sb.Append("\r\n") ;
sb.Append("\tstring strSPName = \"" + strTableName + "\" ;\r\n") ;
sb.Append("\tSqlCommand command = new SqlCommand(strSPName,conn) ;\r\n");
sb.Append("\tcommand.CommandType = CommandType.StoredProcedure ;\r\n") ;
sb.Append("\r\n") ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
int iType = (byte)dr["xtype"] ;
string strParaName = dr["name"].ToString() ;
string strName = UpFirstChar(strParaName.TrimStart('@')) ;
string strSqlType = getSqlDBType(iType) ;
string strShortType = getTypeShort(iType) ;
string strvalue = " a" + strShortType + strName ;
int iLen = (Int16)dr["prec"] ;
string strLen = "" ;
if (strShortType == "str")
strLen = strLen + "," + iLen ;
string strCommandAdd = "\tcommand.Parameters.Add(\"" + strParaName + "\"," + strSqlType + strLen + ") ;\r\n";
string strCommandvalue = "\tcommand.Parameters[\"" + strParaName + "\"].value=" + strvalue + " ;\r\n";
string strCommandNull = "\tcommand.Parameters[\"" + strParaName + "\"].value= DBNull.value ;\r\n";
sb.Append(strCommandAdd) ;
if (strShortType == "dt")
sb.Append("\tif (" + strvalue + "!= DateTime.Minvalue )\r\n\t") ;
else if (strShortType == "str")
sb.Append("\tif (" + strvalue + "!= null )\r\n\t") ;
else if (strShortType == "img")
sb.Append("\tif (" + strvalue + "!= null )\r\n\t") ;
else
sb.Append("") ;
sb.Append(strCommandvalue) ;
if (strShortType == "dt" ||strShortType == "str"||strShortType == "img")
{
sb.Append("\telse\r\n\t") ;
sb.Append(strCommandNull) ;
}
sb.Append("\r\n") ;
}
sb.Append(AddCatchString()) ;
sb.Append("}\r\n") ;
return sb.ToString() ;
}
对于存储过程生成结果集的函数如下:
private string BuildSPGetData(DataSet ds)
{
StringBuilder sb = new StringBuilder() ;
string strFuncParam = "" ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
int iType = (byte)dr["xtype"] ;
string strName = UpFirstChar(dr["name"].ToString().TrimStart('@')) ;
string strType = getType(iType) ;
string strSqlType = getSqlDBType(iType) ;
string strShortType = getTypeShort(iType) ;
strFuncParam = strFuncParam + "\r\n\t\t" + strType + " a" + strShortType + strName + ",";
}
strFuncParam = strFuncParam.TrimEnd(',') ;
string strDef = "public DataSet QuerySP_" + strTableName + "(" + strFuncParam + ")\r\n";
sb.Append(strDef) ;
sb.Append("{\r\n") ;
sb.Append("\tSqlConnection conn = SqlConn.Instance().Connection ;\r\n") ;
sb.Append("\r\n") ;
sb.Append("\tstring strSPName = \"" + strTableName + "\" ;\r\n") ;
sb.Append("\tSqlCommand command = new SqlCommand(strSPName,conn) ;\r\n");
sb.Append("\tcommand.CommandType = CommandType.StoredProcedure ;\r\n") ;
sb.Append("\r\n") ;
foreach(DataRow dr in ds.Tables[0].Rows)
{
int iType = (byte)dr["xtype"] ;
string strParaName = dr["name"].ToString() ;
string strName = UpFirstChar(strParaName.TrimStart('@')) ;
string strSqlType = getSqlDBType(iType) ;
string strShortType = getTypeShort(iType) ;
string strvalue = " a" + strShortType + strName ;
int iLen = (Int16)dr["prec"] ;
string strLen = "" ;
if (strShortType == "str")
strLen = strLen + "," + iLen ;
string strCommandAdd = "\tcommand.Parameters.Add(\"" + strParaName + "\"," + strSqlType + strLen + ") ;\r\n";
string strCommandvalue = "\tcommand.Parameters[\"" + strParaName + "\"].value=" + strvalue + " ;\r\n";
string strCommandNull = "\tcommand.Parameters[\"" + strParaName + "\"].value= DBNull.value ;\r\n";
sb.Append(strCommandAdd) ;
if (strShortType == "dt")
sb.Append("\tif (" + strvalue + "!= DateTime.Minvalue )\r\n\t") ;
else if (strShortType == "str")
sb.Append("\tif (" + strvalue + "!= null )\r\n\t") ;
else if (strShortType == "img")
sb.Append("\tif (" + strvalue + "!= null )\r\n\t") ;
else
sb.Append("") ;
sb.Append(strCommandvalue) ;
if (strShortType == "dt" ||strShortType == "str"||strShortType == "img")
{
sb.Append("\telse\r\n\t") ;
sb.Append(strCommandNull) ;
}
sb.Append("\r\n") ;
}
sb.Append("\tSqlDataAdapter sdaResult = new SqlDataAdapter(command) ;\r\n") ;
sb.Append("\tDataSet ds = new DataSet() ;\r\n") ;
sb.Append(AddCatchQueryString()) ;
sb.Append("}\r\n") ;
return sb.ToString() ;
}
下面是生成结果集的执行结果:
public DataSet QuerySP_ddms_GetBank(
int aiPrsn_id)
{
SqlConnection conn = SqlConn.Instance().Connection ;
string strSPName = "ddms_GetBank" ;
SqlCommand command = new SqlCommand(strSPName,conn) ;
command.CommandType = CommandType.StoredProcedure ;
command.Parameters.Add("@prsn_id",SqlDbType.Int ) ;
command.Parameters["@prsn_id"].value= aiPrsn_id ;
SqlDataAdapter sdaResult = new SqlDataAdapter(command) ;
DataSet ds = new DataSet() ;
try
{
sdaResult.Fill(ds) ;
}
catch(Exception e)
{
throw(new Exception("Error in the Database"+e.Message)) ;
}
finally
{
sdaResult.Dispose() ;
}
return ds ;
}
还有两个函数在程序中用到了,如下所示:
private string AddCatchString()
{
StringBuilder sb = new StringBuilder() ;
sb.Append("\ttry\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tconn.Open() ;\r\n") ;
sb.Append("\t\tcommand.ExecuteNonQuery() ;\r\n") ;
sb.Append("\t\treturn true ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\tcatch(Exception e)\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tthrow(new Exception(\"Error in the Database\"+e.Message)) ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\tfinally\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tconn.Close() ;\r\n") ;
sb.Append("\t}\r\n") ;
return sb.ToString() ;
}
private string AddCatchQueryString()
{
StringBuilder sb = new StringBuilder() ;
sb.Append("\ttry\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tsdaResult.Fill(ds) ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\tcatch(Exception e)\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tthrow(new Exception(\"Error in the Database\"+e.Message)) ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\tfinally\r\n") ;
sb.Append("\t{\r\n") ;
sb.Append("\t\tsdaResult.Dispose() ;\r\n") ;
sb.Append("\t}\r\n") ;
sb.Append("\treturn ds ;\r\n") ;
return sb.ToString() ;
}
顺便说一下,文章开头的一段代码就是用这个程序生成的,当然,这种方法还有待完善的地方,希望大家指正。
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