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How do the two LPCTSTR values ​​add up?

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Post time: 2020-1-31 21:00:01
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How do the two LPCTSTR values ​​add up?
E.g
LPCTSTR a1 = _T ("a");
LPCTSTR a2 = _T ("a2");
LPCTSTR a3;

How to add a1 and a2 to a3

Thank you:)
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Post time: 2020-3-18 22:15:01
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strcat
wcscat
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Post time: 2020-3-21 20:15:01
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#include <string>

std :: basic_string <TCHAR> s1 = a1;
std :: basic_string <TCHAR> s2 = a2;
std :: basic_string <TCHAR> s3 = s1 + s2;
LPCTSTR a3 = s3.c_str ();
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Post time: 2020-9-5 11:15:02
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strcat (a1, a2); //string concatenation function
a3=a1;
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Post time: 2020-9-5 11:30:01
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strcat (a1, a2);
a3=a1;
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Post time: 2020-9-5 12:30:01
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Never use strcat, because strcat will modify the content of a1, which means that the first parameter must not be const.
Note that your string is a constant pointer and it points to a string constant. The data stored in the constant area cannot be modified.
And your a3 has no allocated space at all.
First, a3 should be defined as LPTSTR, otherwise it is a constant and cannot be modified. Then use:
a3 = (TCHAR *) malloc(255 * sizeof(TCHAR));
strcpy (a3, a1);
strcat (a1, a2);
That's it.
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Post time: 2020-9-5 12:45:01
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a3 = CString(a1) + a2;
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