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« XPCOM API Reference


The NS_StringAppendData function appends data to the existing value of a nsAString instance. This is a low-level API.

  #include "nsStringAPI.h"

  nsresult NS_StringAppendData(
    nsAString& aString,
    const PRUnichar* aData,
    PRUint32 aDataLength = PR_UINT32_MAX


[in] A nsAString instance to be modified.
[in] A raw character array to copy into this string.
[in] The length of aData, measured in storage units. If equal to PR_UINT32_MAX, then aData is assumed to be null-terminated. Otherwise, aData need not be null terminated.

Return Values

The NS_StringAppendData function returns NS_OK if successful. Otherwise, it returns an error code.


This function is defined inline as a wrapper around NS_StringSetDataRange

Note: GCC requires the -fshort-wchar option to compile this example since PRUnichar is an unsigned short. This example should compile by default under MSVC.

Example Code

  nsStringContainer str;
  NS_StringSetData(str, L"hello");
  NS_StringAppendData(str, L" world");

  const PRUnichar* data;
  NS_StringGetData(str, &data);
  // data now points to the string: L"hello world"



This function was frozen for Mozilla 1.7. See bug 239123 for details.

See Also

NS_StringSetDataRange, nsAString

Document Tags and Contributors

 Contributors to this page: stephaniehobson, Sheppy, Pmash
 Last updated by: stephaniehobson,