[C #] Step-by-step development of your own Automatic Code Generation Tool 2: field and C # variable Conversion

Step 2: Data Table preprocessing

////// Obtain the conversion statement from the database field to the type based on the variable type //////Private Static void initconvertmethod (fieldmodel field) {Switch (field. vartype) {Case "string": field. tovarconvertmethod = "convert. tostring "; break; Case" int ": field. tovarconvertmethod = "convert. toint32 "; break; Case" datetime ": field. tovarconvertmethod = "convert. todatetime "; break; Case" bool ": field. tovarconvertmethod = "convert. toboolean "; break; Case" float ": field. tovarconvertmethod = "C Onvert. tosingle "; break; Case" decimal ": field. tovarconvertmethod = "convert. todecimal "; break; Case" byte [] ": field. tovarconvertmethod = "(byte [])"; break; Case "money": field. tovarconvertmethod = "convert. todecimal "; break; default: Throw new exception (string. the conversion method for format ("variable type ({0}) is not defined! ", Field. vartype ));}}////// Initialize the default value of the database object class attribute //////Database entity attributes Private Static void initdefavarvarvalue (fieldmodel field) {Switch (field. dbtype) {Case "char": field. defaultvaluevar = "string. empty "; break; Case" nchar ": field. defaultvaluevar = "string. empty "; break; Case" varchar ": field. defaultvaluevar = "string. empty "; break; Case" nvarchar ": field. defaultvaluevar = "string. empty "; break; Case" text ": field. defaultvaluevar = "string. empty "; break; Case "ntext": field. defaultvaluevar = "string. empty "; break; Case" int ": field. defaultvaluevar = "0"; break; Case "bit": field. defaultvaluevar = "false"; break; Case "datetime": field. defaultvaluevar = "datetime. minvalue "; break; Case" float ": field. defaultvaluevar = "0"; break; Case "decimal": field. defaultvaluevar = "0"; break; Case "image": field. defaultvaluevar = "null"; break; Case "money": F Ield. defaultvaluevar = "0"; break; default: Throw new exception (string. Format ("database field type ({0}) undefined! ", Field. dbtype ));}}////// Obtain the data access parameter type /////////
  Private Static string getsqlparamtypefromsqldbtype (string dbtype) {Switch (dbtype. tolower () {Case "char": Return "sqldbtype. char "; Case" nchar ": Return" sqldbtype. nchar "; Case" varchar ": Return" sqldbtype. varchar "; Case" nvarchar ": Return" sqldbtype. nvarchar "; Case" text ": Return" sqldbtype. text "; Case" ntext ": Return" sqldbtype. ntext "; Case" int ": Return" sqldbtype. INT "; Case" bit ": Return" SQL Dbtype. bit "; Case" datetime ": Return" sqldbtype. datetime "; Case" float ": Return" sqldbtype. float "; Case" image ": Return" sqldbtype. image "; Case" decimal ": Return" sqldbtype. decimal "; Case" money ": Return" sqldbtype. money "; default: Throw new exception (string. format ("database field type ({0}) undefined! ", Dbtype ));}}////// Obtain the property variable type /////////
  Private Static string getvartypefromsqldbtype (string dbtype) {Switch (dbtype. tolower () {Case "char": Return "string"; Case "nchar": Return "string"; Case "varchar": Return "string"; Case "nvarchar ": return "string"; Case "text": Return "string"; Case "ntext": Return "string"; Case "int": Return "int"; Case "bit ": return "bool"; Case "datetime": Return "datetime"; Case "float": Return "float"; CA Se "image": Return "byte []"; Case "decimal": Return "decimal"; Case "money": Return "decimal"; default: Throw new exception (string. format ("database field type ({0}) undefined! ", Dbtype ));}}