1+ // This sample code shows a bug in the .NET marshaller.
2+ // Native C++ functions returning a string (char*) sometimes
3+ // are not marshalled correctly throwing an exception.
4+ // This is the reason why the .NET wrapper converts
5+ // the char-pointer manually into a .NET string.
6+
7+ using System ;
8+ using System . Text ;
9+ using System . Runtime . InteropServices ;
10+
11+ public static class FreeImage
12+ {
13+ private const string dllName = "FreeImage.dll" ;
14+
15+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFormatFromFIF" ) ]
16+ [ return : MarshalAs ( UnmanagedType . LPStr ) ]
17+ public static extern string GetFormatFromFIF ( int format ) ;
18+
19+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFIFExtensionList" ) ]
20+ [ return : MarshalAs ( UnmanagedType . LPStr ) ]
21+ public static extern string GetFIFExtensionList ( int format ) ;
22+
23+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFIFDescription" ) ]
24+ [ return : MarshalAs ( UnmanagedType . LPStr ) ]
25+ public static extern string GetFIFDescription ( int format ) ;
26+
27+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFIFRegExpr" ) ]
28+ [ return : MarshalAs ( UnmanagedType . LPStr ) ]
29+ public static extern string GetFIFRegExpr ( int format ) ;
30+
31+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFIFMimeType" ) ]
32+ [ return : MarshalAs ( UnmanagedType . LPStr ) ]
33+ public static extern string GetFIFMimeType ( int format ) ;
34+
35+ [ DllImport ( dllName , EntryPoint = "FreeImage_GetFIFCount" ) ]
36+ public static extern int GetFIFCount ( ) ;
37+ }
38+
39+ public class Program
40+ {
41+ public static bool [ , ] getmatrix ( int fifCount )
42+ {
43+ bool [ , ] matrix = new bool [ 5 , fifCount ] ;
44+
45+ int j = 0 ;
46+
47+ for ( int i = 0 ; i < fifCount ; i ++ )
48+ {
49+ bool success = true ;
50+ try
51+ {
52+ FreeImage . GetFormatFromFIF ( i ) ;
53+ }
54+ catch
55+ {
56+ success = false ;
57+ }
58+ matrix [ j , i ] = success ;
59+ }
60+ j ++ ;
61+
62+ for ( int i = 0 ; i < fifCount ; i ++ )
63+ {
64+ bool success = true ;
65+ try
66+ {
67+ FreeImage . GetFIFExtensionList ( i ) ;
68+ }
69+ catch
70+ {
71+ success = false ;
72+ }
73+ matrix [ j , i ] = success ;
74+ }
75+ j ++ ;
76+
77+ for ( int i = 0 ; i < fifCount ; i ++ )
78+ {
79+ bool success = true ;
80+ try
81+ {
82+ FreeImage . GetFIFDescription ( i ) ;
83+ }
84+ catch
85+ {
86+ success = false ;
87+ }
88+ matrix [ j , i ] = success ;
89+ }
90+ j ++ ;
91+
92+ for ( int i = 0 ; i < fifCount ; i ++ )
93+ {
94+ bool success = true ;
95+ try
96+ {
97+ FreeImage . GetFIFRegExpr ( i ) ;
98+ }
99+ catch
100+ {
101+ success = false ;
102+ }
103+ matrix [ j , i ] = success ;
104+ }
105+ j ++ ;
106+
107+ for ( int i = 0 ; i < fifCount ; i ++ )
108+ {
109+ bool success = true ;
110+ try
111+ {
112+ FreeImage . GetFIFMimeType ( i ) ;
113+ }
114+ catch
115+ {
116+ success = false ;
117+ }
118+ matrix [ j , i ] = success ;
119+ }
120+
121+ return matrix ;
122+ }
123+
124+ public static void Main ( )
125+ {
126+ int fifCount = FreeImage . GetFIFCount ( ) ;
127+ bool [ , ] matrix = getmatrix ( fifCount ) ;
128+
129+ Console . Clear ( ) ;
130+ Console . WriteLine ( "1: GetFormatFromFIF" ) ;
131+ Console . WriteLine ( "2: GetFIFExtensionList" ) ;
132+ Console . WriteLine ( "3: GetFIFDescription" ) ;
133+ Console . WriteLine ( "4: GetFIFRegExpr" ) ;
134+ Console . WriteLine ( "5: GetFIFMimeType" ) ;
135+ Console . Write ( Environment . NewLine ) ;
136+
137+ Console . Write ( "FIF:\t " ) ;
138+ for ( int x = 1 ; x < 6 ; x ++ )
139+ Console . Write ( "{0}:\t " , x ) ;
140+
141+ Console . Write ( Environment . NewLine ) ;
142+
143+ for ( int k = 0 ; k < fifCount ; k ++ )
144+ {
145+ Console . Write ( "{0}:\t " , k ) ;
146+ for ( int l = 0 ; l < 5 ; l ++ )
147+ {
148+ Console . Write ( matrix [ l , k ] ? "1\t " : "0\t " ) ;
149+ }
150+ Console . Write ( Environment . NewLine ) ;
151+ }
152+ }
153+ }
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