| 1 | \section{\class{wxVariant}}\label{wxvariant} |
| 2 | |
| 3 | The {\bf wxVariant} class represents a container for any type. |
| 4 | A variant's value can be changed at run time, possibly to a different type of value. |
| 5 | |
| 6 | As standard, wxVariant can store values of type bool, char, double, long, string, |
| 7 | string list, time, date, void pointer, list of strings, and list of variants. However, an application can extend wxVariant's capabilities by deriving from the class \helpref{wxVariantData}{wxvariantdata} and using the wxVariantData form of the wxVariant constructor or assignment operator to assign this data to a variant. Actual values for user-defined types will need to be accessed via the wxVariantData object, unlike the case for basic data types where convenience functions such as GetLong can be used. |
| 8 | |
| 9 | This class is useful for reducing the programming for certain tasks, such as an editor |
| 10 | for different data types, or a remote procedure call protocol. |
| 11 | |
| 12 | An optional name member is associated with a wxVariant. This might be used, for example, in CORBA |
| 13 | or OLE automation classes, where named parameters are required. |
| 14 | |
| 15 | \wxheading{Derived from} |
| 16 | |
| 17 | \helpref{wxObject}{wxobject} |
| 18 | |
| 19 | \wxheading{Include files} |
| 20 | |
| 21 | <wx/variant.h> |
| 22 | |
| 23 | \wxheading{See also} |
| 24 | |
| 25 | \helpref{wxVariantData}{wxvariantdata} |
| 26 | |
| 27 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 28 | |
| 29 | \membersection{wxVariant::wxVariant}\label{wxvariantctor} |
| 30 | |
| 31 | \func{}{wxVariant}{\void} |
| 32 | |
| 33 | Default constructor. |
| 34 | |
| 35 | \func{}{wxVariant}{\param{const wxVariant\& }{variant}} |
| 36 | |
| 37 | Copy constructor. |
| 38 | |
| 39 | \func{}{wxVariant}{\param{const char*}{ value}, \param{const wxString\& }{name = ``"}} |
| 40 | |
| 41 | \func{}{wxVariant}{\param{const wxString\&}{ value}, \param{const wxString\& }{name = ``"}} |
| 42 | |
| 43 | Construction from a string value. |
| 44 | |
| 45 | \func{}{wxVariant}{\param{char}{ value}, \param{const wxString\& }{name = ``"}} |
| 46 | |
| 47 | Construction from a character value. |
| 48 | |
| 49 | \func{}{wxVariant}{\param{long}{ value}, \param{const wxString\& }{name = ``"}} |
| 50 | |
| 51 | Construction from an integer value. You may need to cast to (long) to |
| 52 | avoid confusion with other constructors (such as the bool constructor). |
| 53 | |
| 54 | \func{}{wxVariant}{\param{bool}{ value}, \param{const wxString\& }{name = ``"}} |
| 55 | |
| 56 | Construction from a boolean value. |
| 57 | |
| 58 | \func{}{wxVariant}{\param{double}{ value}, \param{const wxString\& }{name = ``"}} |
| 59 | |
| 60 | Construction from a double-precision floating point value. |
| 61 | |
| 62 | \func{}{wxVariant}{\param{const wxList\&}{ value}, \param{const wxString\& }{name = ``"}} |
| 63 | |
| 64 | Construction from a list of wxVariant objects. This constructor |
| 65 | copies {\it value}, the application is still responsible for |
| 66 | deleting {\it value} and its contents. |
| 67 | |
| 68 | \func{}{wxVariant}{\param{void*}{ value}, \param{const wxString\& }{name = ``"}} |
| 69 | |
| 70 | Construction from a void pointer. |
| 71 | |
| 72 | \func{}{wxVariant}{\param{wxObject*}{ value}, \param{const wxString\& }{name = ``"}} |
| 73 | |
| 74 | Construction from a wxObject pointer. |
| 75 | |
| 76 | \func{}{wxVariant}{\param{wxVariantData*}{ data}, \param{const wxString\& }{name = ``"}} |
| 77 | |
| 78 | Construction from user-defined data. The variant holds onto the {\it data} pointer. |
| 79 | |
| 80 | \func{}{wxVariant}{\param{wxDateTime\&}{ val}, \param{const wxString\& }{name = ``"}} |
| 81 | |
| 82 | Construction from a \helpref{wxDateTime}{wxdatetime}. |
| 83 | |
| 84 | \func{}{wxVariant}{\param{wxArrayString\&}{ val}, \param{const wxString\& }{name = ``"}} |
| 85 | |
| 86 | Construction from an array of strings. This constructor copies {\it value} and its contents. |
| 87 | |
| 88 | \func{}{wxVariant}{\param{DATE\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}} |
| 89 | |
| 90 | Construction from a odbc date value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value. |
| 91 | |
| 92 | \func{}{wxVariant}{\param{TIME\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}} |
| 93 | |
| 94 | Construction from a odbc time value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value. |
| 95 | |
| 96 | \func{}{wxVariant}{\param{TIMESTAMP\_STRUCT*}{ val}, \param{const wxString\& }{name = ``"}} |
| 97 | |
| 98 | Construction from a odbc timestamp value. Represented internally by a \helpref{wxDateTime}{wxdatetime} value. |
| 99 | |
| 100 | \membersection{wxVariant::\destruct{wxVariant}}\label{wxvariantdtor} |
| 101 | |
| 102 | \func{}{\destruct{wxVariant}}{\void} |
| 103 | |
| 104 | Destructor. |
| 105 | |
| 106 | |
| 107 | \membersection{wxVariant::Append}\label{wxvariantappend} |
| 108 | |
| 109 | \func{void}{Append}{\param{const wxVariant\&}{ value}} |
| 110 | |
| 111 | Appends a value to the list. |
| 112 | |
| 113 | \membersection{wxVariant::ClearList}\label{wxvariantclearlist} |
| 114 | |
| 115 | \func{void}{ClearList}{\void} |
| 116 | |
| 117 | Deletes the contents of the list. |
| 118 | |
| 119 | |
| 120 | \membersection{wxVariant::Convert}\label{wxvariantconvert} |
| 121 | |
| 122 | \constfunc{bool}{Convert}{\param{long*}{ value}} |
| 123 | |
| 124 | \constfunc{bool}{Convert}{\param{bool*}{ value}} |
| 125 | |
| 126 | \constfunc{bool}{Convert}{\param{double*}{ value}} |
| 127 | |
| 128 | \constfunc{bool}{Convert}{\param{wxString*}{ value}} |
| 129 | |
| 130 | \constfunc{bool}{Convert}{\param{char*}{ value}} |
| 131 | |
| 132 | \constfunc{bool}{Convert}{\param{wxDateTime*}{ value}} |
| 133 | |
| 134 | Retrieves and converts the value of this variant to the type that {\it value} is. |
| 135 | |
| 136 | |
| 137 | \membersection{wxVariant::GetCount}\label{wxvariantgetcount} |
| 138 | |
| 139 | \constfunc{int}{GetCount}{\void} |
| 140 | |
| 141 | Returns the number of elements in the list. |
| 142 | |
| 143 | \membersection{wxVariant::Delete}\label{wxvariantdelete} |
| 144 | |
| 145 | \func{bool}{Delete}{\param{int }{item}} |
| 146 | |
| 147 | Deletes the zero-based {\it item} from the list. |
| 148 | |
| 149 | \membersection{wxVariant::GetArrayString}\label{wxvariantgetarraystring} |
| 150 | |
| 151 | \constfunc{wxArrayString}{GetArrayString}{\void} |
| 152 | |
| 153 | Returns the string array value. |
| 154 | |
| 155 | \membersection{wxVariant::GetBool}\label{wxvariantgetbool} |
| 156 | |
| 157 | \constfunc{bool}{GetBool}{\void} |
| 158 | |
| 159 | Returns the boolean value. |
| 160 | |
| 161 | \membersection{wxVariant::GetChar}\label{wxvariantgetchar} |
| 162 | |
| 163 | \constfunc{char}{GetChar}{\void} |
| 164 | |
| 165 | Returns the character value. |
| 166 | |
| 167 | \membersection{wxVariant::GetData}\label{wxvariantgetdata} |
| 168 | |
| 169 | \constfunc{wxVariantData*}{GetData}{\void} |
| 170 | |
| 171 | Returns a pointer to the internal variant data. |
| 172 | |
| 173 | \membersection{wxVariant::GetDateTime}\label{wxvariantgetdatetime} |
| 174 | |
| 175 | \constfunc{wxDateTime}{GetDateTime}{\void} |
| 176 | |
| 177 | Returns the date value. |
| 178 | |
| 179 | \membersection{wxVariant::GetDouble}\label{wxvariantgetdouble} |
| 180 | |
| 181 | \constfunc{double}{GetDouble}{\void} |
| 182 | |
| 183 | Returns the floating point value. |
| 184 | |
| 185 | \membersection{wxVariant::GetLong}\label{wxvariantgetlong} |
| 186 | |
| 187 | \constfunc{long}{GetLong}{\void} |
| 188 | |
| 189 | Returns the integer value. |
| 190 | |
| 191 | \membersection{wxVariant::GetName}\label{wxvariantgetname} |
| 192 | |
| 193 | \constfunc{const wxString\&}{GetName}{\void} |
| 194 | |
| 195 | Returns a constant reference to the variant name. |
| 196 | |
| 197 | \membersection{wxVariant::GetString}\label{wxvariantgetstring} |
| 198 | |
| 199 | \constfunc{wxString}{GetString}{\void} |
| 200 | |
| 201 | Gets the string value. |
| 202 | |
| 203 | \membersection{wxVariant::GetType}\label{wxvariantgettype} |
| 204 | |
| 205 | \constfunc{wxString}{GetType}{\void} |
| 206 | |
| 207 | Returns the value type as a string. The built-in types are: bool, char, date, double, list, long, string, stringlist, time, void*. |
| 208 | |
| 209 | If the variant is null, the value type returned is the string ``null" (not the empty string). |
| 210 | |
| 211 | \membersection{wxVariant::GetVoidPtr}\label{wxvariantgetvoidptr} |
| 212 | |
| 213 | \constfunc{void*}{GetVoidPtr}{\void} |
| 214 | |
| 215 | Gets the void pointer value. |
| 216 | |
| 217 | \membersection{wxVariant::GetWxObjectPtr}\label{wxvariantgetwxobjectptr} |
| 218 | |
| 219 | \constfunc{void*}{GetWxObjectPtr}{\void} |
| 220 | |
| 221 | Gets the wxObject pointer value. |
| 222 | |
| 223 | \membersection{wxVariant::Insert}\label{wxvariantinsert} |
| 224 | |
| 225 | \func{void}{Insert}{\param{const wxVariant\&}{ value}} |
| 226 | |
| 227 | Inserts a value at the front of the list. |
| 228 | |
| 229 | \membersection{wxVariant::IsNull}\label{wxvariantisnull} |
| 230 | |
| 231 | \constfunc{bool}{IsNull}{\void} |
| 232 | |
| 233 | Returns true if there is no data associated with this variant, false if there is data. |
| 234 | |
| 235 | \membersection{wxVariant::IsType}\label{wxvariantistype} |
| 236 | |
| 237 | \constfunc{bool}{IsType}{\param{const wxString\&}{ type}} |
| 238 | |
| 239 | Returns true if {\it type} matches the type of the variant, false otherwise. |
| 240 | |
| 241 | \membersection{wxVariant::IsValueKindOf}\label{wxvariantisvaluekindof} |
| 242 | |
| 243 | \constfunc{bool}{IsValueKindOf}{\param{const wxClassInfo* type}{ type}} |
| 244 | |
| 245 | Returns true if the data is derived from the class described by {\it type}, false otherwise. |
| 246 | |
| 247 | \membersection{wxVariant::MakeNull}\label{wxvariantmakenull} |
| 248 | |
| 249 | \func{void}{MakeNull}{\void} |
| 250 | |
| 251 | Makes the variant null by deleting the internal data. |
| 252 | |
| 253 | \membersection{wxVariant::MakeString}\label{wxvariantmakestring} |
| 254 | |
| 255 | \constfunc{wxString}{MakeString}{\void} |
| 256 | |
| 257 | Makes a string representation of the variant value (for any type). |
| 258 | |
| 259 | \membersection{wxVariant::Member}\label{wxvariantmember} |
| 260 | |
| 261 | \constfunc{bool}{Member}{\param{const wxVariant\&}{ value}} |
| 262 | |
| 263 | Returns true if {\it value} matches an element in the list. |
| 264 | |
| 265 | \membersection{wxVariant::NullList}\label{wxvariantnulllist} |
| 266 | |
| 267 | \func{void}{NullList}{\void} |
| 268 | |
| 269 | Makes an empty list. This differs from a null variant which has no data; a null list |
| 270 | is of type list, but the number of elements in the list is zero. |
| 271 | |
| 272 | \membersection{wxVariant::SetData}\label{wxvariantsetdata} |
| 273 | |
| 274 | \func{void}{SetData}{\param{wxVariantData*}{ data}} |
| 275 | |
| 276 | Sets the internal variant data, deleting the existing data if there is any. |
| 277 | |
| 278 | \membersection{wxVariant::operator $=$}\label{wxvariantassignment} |
| 279 | |
| 280 | \func{void}{operator $=$}{\param{const wxVariant\& }{value}} |
| 281 | |
| 282 | \func{void}{operator $=$}{\param{wxVariantData* }{value}} |
| 283 | |
| 284 | \func{void}{operator $=$}{\param{const wxString\& }{value}} |
| 285 | |
| 286 | \func{void}{operator $=$}{\param{const char* }{value}} |
| 287 | |
| 288 | \func{void}{operator $=$}{\param{char }{value}} |
| 289 | |
| 290 | \func{void}{operator $=$}{\param{const long }{value}} |
| 291 | |
| 292 | \func{void}{operator $=$}{\param{const bool }{value}} |
| 293 | |
| 294 | \func{void}{operator $=$}{\param{const double }{value}} |
| 295 | |
| 296 | \func{void}{operator $=$}{\param{void* }{value}} |
| 297 | |
| 298 | \func{void}{operator $=$}{\param{const wxList\& }{value}} |
| 299 | |
| 300 | \func{void}{operator $=$}{\param{const wxDateTime\& }{value}} |
| 301 | |
| 302 | \func{void}{operator $=$}{\param{const wxArrayString\& }{value}} |
| 303 | |
| 304 | \func{void}{operator $=$}{\param{const DATE\_STRUCT* }{value}} |
| 305 | |
| 306 | \func{void}{operator $=$}{\param{const TIME\_STRUCT* }{value}} |
| 307 | |
| 308 | \func{void}{operator $=$}{\param{const TIMESTAMP\_STRUCT* }{value}} |
| 309 | |
| 310 | Assignment operators. |
| 311 | |
| 312 | \membersection{wxVariant::operator $==$}\label{wxvarianteq} |
| 313 | |
| 314 | \constfunc{bool}{operator $==$}{\param{const wxVariant\& }{value}} |
| 315 | |
| 316 | \constfunc{bool}{operator $==$}{\param{const wxString\& }{value}} |
| 317 | |
| 318 | \constfunc{bool}{operator $==$}{\param{const char* }{value}} |
| 319 | |
| 320 | \constfunc{bool}{operator $==$}{\param{char }{value}} |
| 321 | |
| 322 | \constfunc{bool}{operator $==$}{\param{const long }{value}} |
| 323 | |
| 324 | \constfunc{bool}{operator $==$}{\param{const bool }{value}} |
| 325 | |
| 326 | \constfunc{bool}{operator $==$}{\param{const double }{value}} |
| 327 | |
| 328 | \constfunc{bool}{operator $==$}{\param{void* }{value}} |
| 329 | |
| 330 | \constfunc{bool}{operator $==$}{\param{const wxList\& }{value}} |
| 331 | |
| 332 | \constfunc{bool}{operator $==$}{\param{const wxArrayString\& }{value}} |
| 333 | |
| 334 | \constfunc{bool}{operator $==$}{\param{const wxDateTime\& }{value}} |
| 335 | |
| 336 | Equality test operators. |
| 337 | |
| 338 | \membersection{wxVariant::operator $!=$}\label{wxvariantneq} |
| 339 | |
| 340 | \constfunc{bool}{operator $!=$}{\param{const wxVariant\& }{value}} |
| 341 | |
| 342 | \constfunc{bool}{operator $!=$}{\param{const wxString\& }{value}} |
| 343 | |
| 344 | \constfunc{bool}{operator $!=$}{\param{const char* }{value}} |
| 345 | |
| 346 | \constfunc{bool}{operator $!=$}{\param{char }{value}} |
| 347 | |
| 348 | \constfunc{bool}{operator $!=$}{\param{const long }{value}} |
| 349 | |
| 350 | \constfunc{bool}{operator $!=$}{\param{const bool }{value}} |
| 351 | |
| 352 | \constfunc{bool}{operator $!=$}{\param{const double }{value}} |
| 353 | |
| 354 | \constfunc{bool}{operator $!=$}{\param{void* }{value}} |
| 355 | |
| 356 | \constfunc{bool}{operator $!=$}{\param{const wxList\& }{value}} |
| 357 | |
| 358 | \constfunc{bool}{operator $!=$}{\param{const wxArrayString\& }{value}} |
| 359 | |
| 360 | \constfunc{bool}{operator $!=$}{\param{const wxDateTime\& }{value}} |
| 361 | |
| 362 | Inequality test operators. |
| 363 | |
| 364 | \membersection{wxVariant::operator $[]$}\label{wxvariantarray} |
| 365 | |
| 366 | \constfunc{wxVariant}{operator $[]$}{\param{size\_t }{idx}} |
| 367 | |
| 368 | Returns the value at {\it idx} (zero-based). |
| 369 | |
| 370 | \func{wxVariant\&}{operator $[]$}{\param{size\_t }{idx}} |
| 371 | |
| 372 | Returns a reference to the value at {\it idx} (zero-based). This can be used |
| 373 | to change the value at this index. |
| 374 | |
| 375 | \membersection{wxVariant::operator char}\label{wxvariantchar} |
| 376 | |
| 377 | \constfunc{char}{operator char}{\void} |
| 378 | |
| 379 | Operator for implicit conversion to a char, using \helpref{wxVariant::GetChar}{wxvariantgetchar}. |
| 380 | |
| 381 | \membersection{wxVariant::operator double}\label{wxvariantdouble} |
| 382 | |
| 383 | \constfunc{double}{operator double}{\void} |
| 384 | |
| 385 | Operator for implicit conversion to a double, using \helpref{wxVariant::GetDouble}{wxvariantgetdouble}. |
| 386 | |
| 387 | \constfunc{long}{operator long}{\void} |
| 388 | |
| 389 | Operator for implicit conversion to a long, using \helpref{wxVariant::GetLong}{wxvariantgetlong}. |
| 390 | |
| 391 | \membersection{wxVariant::operator wxString}\label{wxvariantwxstring} |
| 392 | |
| 393 | \constfunc{wxString}{operator wxString}{\void} |
| 394 | |
| 395 | Operator for implicit conversion to a string, using \helpref{wxVariant::MakeString}{wxvariantmakestring}. |
| 396 | |
| 397 | \membersection{wxVariant::operator void*}\label{wxvariantvoid} |
| 398 | |
| 399 | \constfunc{void*}{operator void*}{\void} |
| 400 | |
| 401 | Operator for implicit conversion to a pointer to a void, using \helpref{wxVariant::GetVoidPtr}{wxvariantgetvoidptr}. |
| 402 | |
| 403 | \membersection{wxVariant::operator wxDateTime}\label{wxvariantdatetime} |
| 404 | |
| 405 | \constfunc{void*}{operator wxDateTime}{\void} |
| 406 | |
| 407 | Operator for implicit conversion to a pointer to a \helpref{wxDateTime}{wxdatetime}, using \helpref{wxVariant::GetDateTime}{wxvariantgetdatetime}. |
| 408 | |
| 409 | \section{\class{wxVariantData}}\label{wxvariantdata} |
| 410 | |
| 411 | The {\bf wxVariantData} is used to implement a new type for wxVariant. Derive from wxVariantData, |
| 412 | and override the pure virtual functions. |
| 413 | |
| 414 | \wxheading{Derived from} |
| 415 | |
| 416 | \helpref{wxObject}{wxobject} |
| 417 | |
| 418 | \wxheading{Include files} |
| 419 | |
| 420 | <wx/variant.h> |
| 421 | |
| 422 | \wxheading{See also} |
| 423 | |
| 424 | \helpref{wxVariant}{wxvariant} |
| 425 | |
| 426 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 427 | |
| 428 | \membersection{wxVariantData::wxVariantData}\label{wxvariantdatactor} |
| 429 | |
| 430 | \func{}{wxVariantData}{\void} |
| 431 | |
| 432 | Default constructor. |
| 433 | |
| 434 | \membersection{wxVariantData::Copy}\label{wxvariantdatacopy} |
| 435 | |
| 436 | \func{void}{Copy}{\param{wxVariantData\&}{ data}} |
| 437 | |
| 438 | Copy the data from `this' object to {\it data}. |
| 439 | |
| 440 | \membersection{wxVariantData::Eq}\label{wxvariantdataeq} |
| 441 | |
| 442 | \constfunc{bool}{Eq}{\param{wxVariantData\&}{ data}} |
| 443 | |
| 444 | Returns true if this object is equal to {\it data}. |
| 445 | |
| 446 | \membersection{wxVariantData::GetType}\label{wxvariantdatagettype} |
| 447 | |
| 448 | \constfunc{wxString}{GetType}{\void} |
| 449 | |
| 450 | Returns the string type of the data. |
| 451 | |
| 452 | \membersection{wxVariantData::GetValueClassInfo}\label{wxvariantdatagetvalueclassinfo} |
| 453 | |
| 454 | \constfunc{wxClassInfo*}{GetValueClassInfo}{\void} |
| 455 | |
| 456 | If the data is a wxObject returns a pointer to the objects wxClassInfo structure, if |
| 457 | the data isn't a wxObject the method returns NULL. |
| 458 | |
| 459 | \membersection{wxVariantData::Read}\label{wxvariantdataread} |
| 460 | |
| 461 | \func{bool}{Read}{\param{ostream\&}{ stream}} |
| 462 | |
| 463 | \func{bool}{Read}{\param{wxString\&}{ string}} |
| 464 | |
| 465 | Reads the data from {\it stream} or {\it string}. |
| 466 | |
| 467 | \membersection{wxVariantData::Write}\label{wxvariantdatawrite} |
| 468 | |
| 469 | \constfunc{bool}{Write}{\param{ostream\&}{ stream}} |
| 470 | |
| 471 | \constfunc{bool}{Write}{\param{wxString\&}{ string}} |
| 472 | |
| 473 | Writes the data to {\it stream} or {\it string}. |
| 474 | |
| 475 | |
| 476 | \membersection{wxGetVariantCast}\label{wxgetvariantcast} |
| 477 | |
| 478 | \func{classname *}{wxGetVariantCast}{wxVariant\&, classname} |
| 479 | |
| 480 | This macro returns the data stored in {\it variant} cast to the type {\it classname *} if |
| 481 | the data is of this type (the check is done during the run-time) or |
| 482 | {\tt NULL} otherwise. |
| 483 | |
| 484 | |
| 485 | \wxheading{See also} |
| 486 | |
| 487 | \helpref{RTTI overview}{runtimeclassoverview}\\ |
| 488 | \helpref{wxDynamicCast}{wxdynamiccast} |
| 489 | |