Playing MP3 (C #)

2. The source code is as follows: <reproduced>
6. 1. Media playing class composed of mcisendstring using the API function.
10. ProgramCode
14. Using system;
16. Using system. runtime. interopservices;
18. Using system. text;
20. Using system. IO;
22. Namespace clsmciplay
24. {
26. /// <Summary>
28. /// Summary of clsmci.
30. /// </Summary>
32. Public class clsmci
34. {
36. Public clsmci ()
38. {
40. //
42. // Todo: add the constructor logic here
44. //
46. }
50. // Define the string variable used by the API Function
52. [Financialas (unmanagedtype. byvaltstr, sizeconst = 260)]
54. Private string name = "";
56. [Financialas (unmanagedtype. byvaltstr, sizeconst = 128)]
58. Private string durlength = "";
60. [Financialas (unmanagedtype. lptstr, sizeconst = 128)]
62. Private string temstr = "";
64. Int ilong;
66. // Defines the enumerated variables of the playback status.
68. Public Enum state
70. {
72. Mplaying = 1,
74. Mpuase = 2,
76. Mstop = 3
78. };
80. // Structure Variable
82. Public struct structmci
84. {
86. Public bool bmut;
88. Public int idur;
90. Public int IPOs;
92. Public int ivol;
94. Public int ibal;
96. Public String INAME;
98. Public state;
100. };
104. Public structmci MC = new structmci ();
108. // Obtain the playback file attributes
110. Public String filename
112. {
114. Get
116. {
118. Return MC. INAME;
120. }
122. Set
124. {
126. // Asciiencoding ASC = new asciiencoding ();
128. Try
130. {
132. Temstr = "";
134. Temstr = temstr. padleft (127, convert. tochar (""));
136. Name = Name. padleft (260, convert. tochar (""));
138. MC. INAME = value;
140. Ilong = apiclass. getw.pathname (MC. INAME, name, name. Length );
142. Name = getcurrpath (name );
144. // Name = "open" + convert. tochar (34) + name + convert. tochar (34) + "alias Media ";
146. Name = "open" + convert. tochar (34) + name + convert. tochar (34) + "alias Media ";
148. Ilong = apiclass. mcisendstring ("close all", temstr, temstr. length, 0 );
150. Ilong = apiclass. mcisendstring (name, temstr, temstr. length, 0 );
152. Ilong = apiclass. mcisendstring ("set media time format milliseconds", temstr, temstr. length, 0 );
154. MC. State = state. mstop;
156. }
158. Catch
160. {
162. MessageBox. Show ("error! ");
164. }
166. }
168. }
170. // Play
172. Public void play ()
174. {
176. Temstr = "";
178. Temstr = temstr. padleft (127, convert. tochar (""));
180. Apiclass. mcisendstring ("play media", temstr, temstr. length, 0 );
182. MC. State = state. mplaying;
184. }
186. // Stop
188. Public void stopt ()
190. {
192. Temstr = "";
194. Temstr = temstr. padleft (128, convert. tochar (""));
196. Ilong = apiclass. mcisendstring ("close media", temstr, 128, 0 );
198. Ilong = apiclass. mcisendstring ("close all", temstr, 128, 0 );
200. MC. State = state. mstop;
202. }
206. Public void puase ()
208. {
210. Temstr = "";
212. Temstr = temstr. padleft (128, convert. tochar (""));
214. Ilong = apiclass. mcisendstring ("Pause Media", temstr, temstr. length, 0 );
216. MC. State = state. mpuase;
218. }
220. Private string getcurrpath (string name)
222. {
224. If (name. Length <1) Return "";
226. Name = Name. Trim ();
228. Name = Name. substring (0, name. Length-1 );
230. Return name;
232. }
234. // Total time
236. Public int duration
238. {
240. Get
242. {
244. Durlength = "";
246. Durlength = durlength. padleft (128, convert. tochar (""));
248. Apiclass. mcisendstring ("status media length", durlength, durlength. length, 0 );
250. Durlength = durlength. Trim ();
252. If (durlength = "") return 0;
254. Return (INT) (convert. todouble (durlength)/1000f );
256. }
258. }
262. // Current time
264. Public int currentposition
266. {
268. Get
270. {
272. Durlength = "";
274. Durlength = durlength. padleft (128, convert. tochar (""));
276. Apiclass. mcisendstring ("status Media Position", durlength, durlength. length, 0 );
278. MC. IPOs = (INT) (convert. todouble (durlength)/1000f );
280. Return MC. IPOs;
282. }
284. }
286. }
290. Public class apiclass
292. {
294. [Dllimport ("kernel32.dll", charset = charset. Auto)]
296. Public static extern int getaskpathname (
298. String lpszlongpath,
300. String delimiter file,
302. Int cchbuffer
304. );
308. [Dllimport ("winmm. dll", entrypoint = "mcisendstring", charset = charset. Auto)]
310. Public static extern int mcisendstring (
312. String lpstrcommand,
314. String lpstrreturnstring,
316. Int ureturnlength,
318. Int hwndcallback
320. );
322. }
324. }