下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
| Constant | Value | Description |
|---|---|---|
| SOAP_1_1 (integer) | 1 | |
| SOAP_1_2 (integer) | 2 | |
| SOAP_PERSISTENCE_SESSION (integer) | 1 | |
| SOAP_PERSISTENCE_REQUEST (integer) | 2 | |
| SOAP_FUNCTIONS_ALL (integer) | 999 | |
| SOAP_ENCODED (integer) | 1 | |
| SOAP_LITERAL (integer) | 2 | |
| SOAP_RPC (integer) | 1 | |
| SOAP_DOCUMENT (integer) | 2 | |
| SOAP_ACTOR_NEXT (integer) | 1 | |
| SOAP_ACTOR_NONE (integer) | 2 | |
| SOAP_ACTOR_UNLIMATERECEIVER (integer) | 3 | |
| SOAP_COMPRESSION_ACCEPT (integer) | 32 | |
| SOAP_COMPRESSION_GZIP (integer) | 0 | |
| SOAP_COMPRESSION_DEFLATE (integer) | 16 | |
| SOAP_AUTHENTICATION_BASIC (integer) | 0 | |
| SOAP_AUTHENTICATION_DIGEST (integer) | 1 | |
| UNKNOWN_TYPE (integer) | 999998 | |
| XSD_STRING (integer) | 101 | |
| XSD_BOOLEAN (integer) | 102 | |
| XSD_DECIMAL (integer) | 103 | |
| XSD_FLOAT (integer) | 104 | |
| XSD_DOUBLE (integer) | 105 | |
| XSD_DURATION (integer) | 106 | |
| XSD_DATETIME (integer) | 107 | |
| XSD_TIME (integer) | 108 | |
| XSD_DATE (integer) | 109 | |
| XSD_GYEARMONTH (integer) | 110 | |
| XSD_GYEAR (integer) | 111 | |
| XSD_GMONTHDAY (integer) | 112 | |
| XSD_GDAY (integer) | 113 | |
| XSD_GMONTH (integer) | 114 | |
| XSD_HEXBINARY (integer) | 115 | |
| XSD_BASE64BINARY (integer) | 116 | |
| XSD_ANYURI (integer) | 117 | |
| XSD_QNAME (integer) | 118 | |
| XSD_NOTATION (integer) | 119 | |
| XSD_NORMALIZEDSTRING (integer) | 120 | |
| XSD_TOKEN (integer) | 121 | |
| XSD_LANGUAGE (integer) | 122 | |
| XSD_NMTOKEN (integer) | 123 | |
| XSD_NAME (integer) | 124 | |
| XSD_NCNAME (integer) | 125 | |
| XSD_ID (integer) | 126 | |
| XSD_IDREF (integer) | 127 | |
| XSD_IDREFS (integer) | 128 | |
| XSD_ENTITY (integer) | 129 | |
| XSD_ENTITIES (integer) | 130 | |
| XSD_INTEGER (integer) | 131 | |
| XSD_NONPOSITIVEINTEGER (integer) | 132 | |
| XSD_NEGATIVEINTEGER (integer) | 133 | |
| XSD_LONG (integer) | 134 | |
| XSD_INT (integer) | 135 | |
| XSD_SHORT (integer) | 136 | |
| XSD_BYTE (integer) | 137 | |
| XSD_NONNEGATIVEINTEGER (integer) | 138 | |
| XSD_UNSIGNEDLONG (integer) | 139 | |
| XSD_UNSIGNEDINT (integer) | 140 | |
| XSD_UNSIGNEDSHORT (integer) | 141 | |
| XSD_UNSIGNEDBYTE (integer) | 142 | |
| XSD_POSITIVEINTEGER (integer) | 143 | |
| XSD_NMTOKENS (integer) | 144 | |
| XSD_ANYTYPE (integer) | 145 | |
| XSD_ANYXML (integer) | 147 | |
| APACHE_MAP (integer) | 200 | |
| SOAP_ENC_OBJECT (integer) | 301 | |
| SOAP_ENC_ARRAY (integer) | 300 | |
| XSD_1999_TIMEINSTANT (integer) | 401 | |
| XSD_NAMESPACE (integer) | http://www.w3.org/2001/XMLSchema | |
| XSD_1999_NAMESPACE (integer) | http://www.w3.org/1999/XMLSchema | |
| SOAP_SINGLE_ELEMENT_ARRAYS (integer) | 1 | |
| SOAP_WAIT_ONE_WAY_CALLS (integer) | 2 | |
| SOAP_USE_XSI_ARRAY_TYPE (integer) | 4 | |
| WSDL_CACHE_NONE (integer) | 0 | |
| WSDL_CACHE_DISK (integer) | 1 | |
| WSDL_CACHE_MEMORY (integer) | 2 | |
| WSDL_CACHE_BOTH (integer) | 3 |