mcs/class/Mono.Data.PostgreSqlClient/Mono.Data.PostgreSqlClient/ParmUtil.cs

   1 //\r
   2 // ParmUtil.cs - utility to bind variables in a SQL statement to parameters in C# code\r
   3 //               This is in the PostgreSQL .NET Data provider in Mono\r
   4 //\r
   5 // Author: \r
   6 //    Daniel Morgan <danmorg@sc.rr.com>\r
   7 //\r
   8 // (c)copyright 2002 Daniel Morgan\r
   9 //\r
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31 \r
  32 // comment DEBUG_ParmUtil for production, for debug messages, uncomment\r
  33 //#define DEBUG_ParmUtil\r
  34 \r
  35 using System;\r
  36 using System.Data;\r
  37 using System.Text;\r
  38 \r
  39 namespace Mono.Data.PostgreSqlClient {\r
  40 \r
  41         enum PostgresBindVariableCharacter {\r
  42                 Semicolon,\r
  43                 At,\r
  44                 QuestionMark\r
  45         }\r
  46 \r
  47         public class ParmUtil {\r
  48 \r
  49                 private string sql = "";\r
  50                 private string resultSql = "";\r
  51                 private PgSqlParameterCollection parmsCollection = null;\r
  52                 \r
  53                 static private PostgresBindVariableCharacter PgbindChar = PostgresBindVariableCharacter.Semicolon;\r
  54                 static char bindChar;\r
  55 \r
  56                 // static constructor\r
  57                 static ParmUtil() {\r
  58                         switch(PgbindChar) {\r
  59                         case PostgresBindVariableCharacter.Semicolon:\r
  60                                 bindChar = ':';\r
  61                                 break;\r
  62                         case PostgresBindVariableCharacter.At:\r
  63                                 bindChar = '@';\r
  64                                 break;\r
  65                         case PostgresBindVariableCharacter.QuestionMark:\r
  66                                 // this doesn't have named parameters,\r
  67                                 // they must be in order\r
  68                                 bindChar = '?';\r
  69                                 break;\r
  70                         }\r
  71                 }\r
  72                                 \r
  73                 public ParmUtil(string query, PgSqlParameterCollection parms) {\r
  74                         sql = query;\r
  75                         parmsCollection = parms;\r
  76                 }\r
  77                 \r
  78                 public string ResultSql {\r
  79                         get {\r
  80                                 return resultSql;\r
  81                         }\r
  82                 }\r
  83 \r
  84                 // TODO: currently only works for input variables,\r
  85                 //       need to do input/output, output, and return\r
  86                 public string ReplaceWithParms() {\r
  87 \r
  88                         StringBuilder result = new StringBuilder();\r
  89                         char[] chars = sql.ToCharArray();\r
  90                         bool bStringConstFound = false;\r
  91 \r
  92                         for(int i = 0; i < chars.Length; i++) {\r
  93                                 if(chars[i] == '\'') {\r
  94                                         if(bStringConstFound == true)\r
  95                                                 bStringConstFound = false;\r
  96                                         else\r
  97                                                 bStringConstFound = true;\r
  98 \r
  99                                         result.Append(chars[i]);\r
 100                                 }\r
 101                                 else if(chars[i] == bindChar && \r
 102                                         bStringConstFound == false) {\r
 103 #if DEBUG_ParmUtil\r
 104                                         Console.WriteLine("Bind Variable character found...");\r
 105 #endif                                  \r
 106                                         StringBuilder parm = new StringBuilder();\r
 107                                         i++;\r
 108                                         while(i <= chars.Length) {\r
 109                                                 char ch;\r
 110                                                 if(i == chars.Length)\r
 111                                                         ch = ' '; // a space\r
 112                                                 else\r
 113                                                         ch = chars[i];\r
 114 \r
 115 #if DEBUG_ParmUtil                                              \r
 116                                                 Console.WriteLine("Is char Letter or digit?");\r
 117 #endif                                          \r
 118                                                 if(Char.IsLetterOrDigit(ch)) {\r
 119 #if DEBUG_ParmUtil\r
 120                                                         Console.WriteLine("Char IS letter or digit. " + \r
 121                                                                 "Now, append char to parm StringBuilder");\r
 122 #endif\r
 123                                                         parm.Append(ch);\r
 124                                                 }\r
 125                                                 else {\r
 126 #if DEBUG_ParmUtil\r
 127                                                         Console.WriteLine("Char is NOT letter or char. " + \r
 128                                                                 "thus we got rest of bind variable name. ");\r
 129                                                                 \r
 130                                                         // replace bind variable placeholder \r
 131                                                         // with data value constant\r
 132                                                         Console.WriteLine("parm StringBuilder to string p...");\r
 133 #endif\r
 134                                                         string p = parm.ToString();\r
 135 #if DEBUG_ParmUtil\r
 136                                                         Console.WriteLine("calling BindReplace...");\r
 137 #endif                                                  \r
 138                                                         bool found = BindReplace(result, p);\r
 139 #if DEBUG_ParmUtil\r
 140                                                         Console.WriteLine("    Found = " + found);\r
 141 #endif\r
 142                                                         if(found == true)\r
 143                                                                 break;\r
 144                                                         else {                                          \r
 145                                                                 // *** Error Handling\r
 146                                                                 Console.WriteLine("Error: parameter not found: " + p);\r
 147                                                                 return "";\r
 148                                                         }\r
 149                                                 }\r
 150                                                 i++;\r
 151                                         }\r
 152                                         i--;\r
 153                                 }\r
 154                                 else \r
 155                                         result.Append(chars[i]);\r
 156                         }\r
 157                         \r
 158                         resultSql = result.ToString();\r
 159                         return resultSql;\r
 160                 }\r
 161 \r
 162                 public bool BindReplace (StringBuilder result, string p) {\r
 163                         // bind variable\r
 164                         bool found = false;\r
 165 \r
 166 #if DEBUG_ParmUtil\r
 167                         Console.WriteLine("Does the parmsCollection contain the parameter???: " + p);\r
 168 #endif\r
 169                         if(parmsCollection.Contains(p) == true) {\r
 170                                 // parameter found\r
 171 #if DEBUG_ParmUtil\r
 172                                 Console.WriteLine("Parameter Found: " + p);\r
 173 #endif\r
 174                                 PgSqlParameter prm = parmsCollection[p];\r
 175 \r
 176 #if DEBUG_ParmUtil                                                                                                                                      \r
 177                                 // DEBUG \r
 178                                 Console.WriteLine("          Value: " + prm.Value);\r
 179                                 Console.WriteLine("      Direction: " + prm.Direction);\r
 180 #endif\r
 181                                 // convert object to string and place\r
 182                                 // into SQL\r
 183                                 if(prm.Direction == ParameterDirection.Input) {\r
 184                                         string strObj = PostgresHelper.\r
 185                                                 ObjectToString(prm.DbType, \r
 186                                                                 prm.Value);\r
 187                                         result.Append(strObj);\r
 188                                 }\r
 189                                 else\r
 190                                         result.Append(bindChar + p);\r
 191 \r
 192                                 found = true;\r
 193                         }\r
 194                         return found;\r
 195                 }\r
 196         }\r
 197 }\r