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nsIVariant and JS types. We mark the interface [scriptable] so that JS can use methods that refer to this interface. But we mark all the methods and attributes [noscript] since any nsIVariant object will be automatically converted to a JS type anyway.
nsISupports
Last changed in Gecko 2.0 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1)Method overview
ACString getAsACString(); Native code only! |
nsresult getAsArray(out PRUint16 type, out nsIID iid, out PRUint32 count, out voidPtr ptr); Violates the XPCOM interface guidelines |
AString getAsAString(); Native code only! |
AUTF8String getAsAUTF8String(); Native code only! |
PRBool getAsBool(); Native code only! |
char getAsChar(); Native code only! |
DOMString getAsDOMString(); Native code only! |
double getAsDouble(); Native code only! |
float getAsFloat(); Native code only! |
nsresult getAsID(out nsID retval); Violates the XPCOM interface guidelines |
PRInt16 getAsInt16(); Native code only! |
PRInt32 getAsInt32(); Native code only! |
PRInt64 getAsInt64(); Native code only! |
PRUint8 getAsInt8(); Native code only! |
void getAsInterface(out nsIIDPtr iid, [iid_is(iid), retval] out nsQIResult iface); Native code only! |
nsISupports getAsISupports(); Native code only! |
jsval getAsJSVal(); Native code only! |
string getAsString(); Native code only! |
void getAsStringWithSize(out PRUint32 size, [size_is(size), retval] out string str); Native code only! |
PRUint16 getAsUint16(); Native code only! |
PRUint32 getAsUint32(); Native code only! |
PRUint64 getAsUint64(); Native code only! |
PRUint8 getAsUint8(); Native code only! |
wchar getAsWChar(); Native code only! |
wstring getAsWString(); Native code only! |
void getAsWStringWithSize(out PRUint32 size, [size_is(size), retval] out wstring str); Native code only! |
Attributes
| Attribute | Type | Description |
dataType |
PRUint16 |
Read only. Native code only! |
Methods
getAsACString
ACString getAsACString();
Parameters
None.
Return value
The value is converted to an 8-bit string in the ISO-8859-1 character set. If the value was UTF16 then the high bits are lost. If the value was UTF8 then it is converted to UTF16 and the high bits are discarded. Arrays and interface pointers cannot be converted to a string.
getAsArray()
nsresult getAsArray( out PRUint16 type, out nsIID iid, out PRUint32 count, out voidPtr ptr );
Parameters
-
type - The type of the array elements.
-
iid - The IID of the array elements, if they are interface pointers.
-
count - The number of elements in the array.
-
ptr - A copy of the array of underlying elements. (Reference counted elements are not cloned, but their reference count is increased.)
Return value
getAsAString
AString getAsAString();
Parameters
None.
Return value
The internal value is converted to a UTF16 string. Arrays and interface pointers cannot be converted to a string.
getAsAUTF8String
AUTF8String getAsAUTF8String();
Parameters
None.
Return value
The internal value is converted to a UTF8 string. An ISO-8859-1 string is widened to a UTF16 string first. Arrays and interface pointers cannot be converted to a string.
getAsBool
PRBool getAsBool();
Parameters
None.
Return value
If possible, the internal value is converted to a double, which is then compared to zero.
getAsChar
char getAsChar();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it is of a numeric type, it is cast directly to char.
getAsDOMString
DOMString getAsDOMString();
Parameters
None.
Return value
This returns the same as the getAsAString method.
getAsDouble
double getAsDouble();
Parameters
None.
Return value
If the internal value is a string, it is converted to a double, if possible. If it is of a numeric type it is cast directly to double.
getAsFloat
float getAsFloat();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it is of a numeric type, it is cast directly to float.
getAsID()
nsresult getAsID( out nsID retval );
Parameters
-
retval - If the internal value is an IID then it is returned. If it is of type interface pointer then then IID of the pointer is returned. If it is of string type then an attempt is made to convert the string to an IID.
Return value
If the conversion succeeds, NS_OK is returned, otherwise NS_ERROR_CANNOT_CONVERT_DATA is returned.
getAsInt16
PRInt16 getAsInt16();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRInt16 then the value is returned.
getAsInt32
PRInt32 getAsInt32();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRInt32 then the value is returned.
getAsInt64
PRInt64 getAsInt64();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it is of a numeric type, it is cast directly to PRInt64.
getAsInt8
PRUint8 getAsInt8();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRInt8 then the value is returned.
getAsInterface
void getAsInterface( out nsIIDPtr iid, [iid_is(iid), retval] out nsQIResult iface );
Parameters
-
iid - The IID of the interface pointer, or nsISupports if no IID was provided.
-
iface - The interface pointer. (The reference count of the object is incremented.)
getAsISupports
nsISupports getAsISupports();
Parameters
None.
Return value
The interface pointer. (The reference count of the object is incremented.)
getAsJSVal
jsval getAsJSVal();
Parameters
None.
Return value
Returns the underlying JS value, if the variant was created by passing a JS object into XPConnect.
getAsString
string getAsString();
Parameters
None.
Return value
The value is converted to an 8-bit string in the ISO-8859-1 character set. If the value was UTF16 then the high bits are lost. If the value was UTF8 then it is converted to UTF16 and the high bits are discarded. Arrays and interface pointers cannot be converted to a string.
getAsStringWithSize
void getAsStringWithSize( out PRUint32 size, [size_is(size), retval] out string str );
Parameters
-
size - The length of the returned string. Useful in case the string contains embedded null characters.
-
str - The value is converted to an 8-bit string in the ISO-8859-1 character set. If the value was UTF16 then the high bits are lost. If the value was UTF8 then it is converted to UTF16 and the high bits are discarded. Arrays and interface pointers cannot be converted to a string.
getAsUint16
PRUint16 getAsUint16();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRUint16 then the value is returned.
getAsUint32
PRUint32 getAsUint32();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRUint64 then the value is returned.
getAsUint64
PRUint64 getAsUint64();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it is of a numeric type, it is cast to PRInt64 and then to PRUint64. Note that this will do strange things with negative numbers, and float and double values greater than the numeric limits of a PRInt64 will not convert correctly.
getAsUint8
PRUint8 getAsUint8();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it within the numeric limits of a PRUint8 then the value is returned.
getAsWChar
wchar getAsWChar();
Parameters
None.
Return value
If the internal value is a string, it is first converted to a double, if possible. If it is of a numeric type, it is cast directly to PRUnichar.
getAsWString
wstring getAsWString();
Parameters
None.
Return value
The internal value is converted to a UTF16 string. Arrays and interface pointers cannot be converted to a string.
getAsWStringWithSize
void getAsWStringWithSize( out PRUint32 size, [size_is(size), retval] out wstring str );
Parameters
-
size - The length of the returned string. Useful in case the string contains embedded null characters.
-
str - The internal value is converted to a UTF16 string. Arrays and interface pointers cannot be converted to a string.