Assign a wchar_t array to QString

[jacky]

I use QString::fromWCharArray(wchar_t*) to assign a wchar_t array to QString but the QString always is empty.

Here is my code:

wchar_t * temp = new wchar_t[4];
    temp[0] = 'a'; temp[1] = 'b'; temp[3] = 'c'; temp[4] = 0;
    QString test;
    test.fromWCharArray(temp);

wchar_t * temp = new wchar_t[4];
    temp[0] = 'a'; temp[1] = 'b'; temp[3] = 'c'; temp[4] = 0;
    QString test;
    test.fromWCharArray(temp);

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The result is test = "". My expectation is test = "abc".

I appreciate very much if anyone could tell me what's wrong.
Many thanks in advance.