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« XPCOM API Reference


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

  #include "nsStringAPI.h"

  nsresult NS_StringInsertData(
    nsACString& aString,
    PRUint32 aOffset,
    const PRUnichar* aData,
    PRUint32 aDataLength = PR_UINT32_MAX


[in] A nsACString instance to be modified.
[in] An offset into the string's internal buffer specifying where to place the given characters.
[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_StringInsertData 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_StringInsertData(str, 5, 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 , nsACString

Document Tags and Contributors

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