asp.net 快速找出DataTable(Excel)中的重复行

publicoverride DataTable GetUserDataDTList(string excelPath) 
02. 
03. { 
04. 
05. excelPath = excelPath.Trim(); 
06. 
07. string filename =null; 
08. 
09. try 
10. 
11. { 
12. 
13. filename = System.Configuration.ConfigurationSettings.AppSettings["filename"].ToString(); 
14. 
15. } 
16. 
17. catch(Exception ex) 
18. 
19. { 
20. 
21. filename =null; 
22. 
23. throw ex; 
24. 
25. } 
26. 
27. DataTable dt =new DataTable(); 
28. 
29. //DataSet ds = new DataSet(); 
30. 
31. if (string.IsNullOrEmpty(excelPath)) 
32. 
33. { 
34. 
35. dt =null ; 
36. 
37. //ds = null; 
38. 
39. } 
40. 
41. else 
42. 
43. { 
44. 
45. try 
46. 
47. { 
48. 
49. string strConn =@"Provider = Microsoft.ACE.OLEDB.12.0;Data Source="+ excelPath +";Extended Properties = 'Excel 12.0;HDR=Yes;IMEX=1;'"; 
50. 
51. using(OleDbConnection oconn =new OleDbConnection(strConn)) 
52. 
53. { 
54. 
55. OleDbCommand ocmd =null; 
56. 
57. oconn.Open(); 
58. 
59. try 
60. 
61. { 
62. 
63. ocmd =new OleDbCommand("SELECT * FROM ["+filename+"$]", oconn);//在web.config中配置 
64. 
65. OleDbDataAdapter oda =new OleDbDataAdapter(ocmd); 
66. 
67. oda.Fill(dt); 
68. 
69. } 
70. 
71. catch(OleDbException oex) 
72. 
73. { 
74. 
75. dt =null; 
76. 
77. throw oex; 
78. 
79. //ds = null; 
80. 
81. } 
82. 
83. finally 
84. 
85. { 
86. 
87. oconn.Close(); 
88. 
89. ocmd.Dispose(); 
90. 
91. } 
92. 
93. } 
94. 
95. } 
96. 
97. catch(Exception ex) 
98. 
99. { 
100. 
101. throw ex; 
102. 
103. } 
104. 
105. } 
106. 
107. //return ds.Tables[0]; 
108. 
109. return dt; 
110. 
111. }

说明：该方法需要一个参数用来获取Excel文件的路径，找到后放到一个DataTable中。  对于第二条，为了提高性能，我是这样实现的，每次遍历时只跟它后面的数据比较，因为它前面的数据已经跟它比较过了，没必要它再跟前面的数据比较

///<summary>
02. 
03. /// 查看Excel文件中重复的数据 
04. 
05. /// 该方法只是比较编号和客户名称，其他字段没有比较 
06. 
07. ///</summary>
08. 
09. ///<param name="excelPath">string：Excel文件路径</param>
10. 
11. ///<returns>ArrayList：重复行组成的动态数组</returns>
12. 
13. publicstatic ArrayList arrCFData(string excelPath) 
14. 
15. { 
16. 
17. ArrayList arrUserData =new ArrayList(); 
18. 
19. excelPath=excelPath.Trim(); 
20. 
21. if (string.IsNullOrEmpty(excelPath)) 
22. 
23. { 
24. 
25. arrUserData =null; 
26. 
27. } 
28. 
29. else 
30. 
31. { 
32. 
33. string ret =null; 
34. 
35. DataTable dtCompInfo =null; 
36. 
37. try 
38. 
39. { 
40. 
41. dtCompInfo = DF.DBFactory.GetCompanyDAO().GetUserDataDTList(excelPath); 
42. 
43. if(dtCompInfo!=null&&dtCompInfo.Rows.Count>0) 
44. 
45. { 
46. 
47. int count = dtCompInfo.Rows.Count; 
48. 
49. int x, y; 
50. 
51. for (int i =0; i < count;i++ ) 
52. 
53. { 
54. 
55. for (int j = i +1; j < count; j++) 
56. 
57. { 
58. 
59. if (dtCompInfo.Rows[i][0].ToString().Equals(dtCompInfo.Rows[j][0].ToString()) && dtCompInfo.Rows[i][3].ToString().Equals(dtCompInfo.Rows[j][3].ToString())) 
60. 
61. { 
62. 
63. x = i +2; 
64. 
65. y = j +2; 
66. 
67. ret =string.Format("Excel数据中第{0}行和第{1}行数据重复",x, y); 
68. 
69. arrUserData.Add(ret); 
70. 
71. break; 
72. 
73. } 
74. 
75. } 
76. 
77. //arrUserData.Add(dtCompInfo.Rows[i][0].ToString() + "出来吧" + dtCompInfo.Rows[i][3].ToString()); 
78. 
79. 
80. 
81. } 
82. 
83. } 
84. 
85. } 
86. 
87. catch(Exception ex) 
88. 
89. { 
90. 
91. ExceptionManager.SaveException(ex, "Company.cs", ex.Message); 
92. 
93. arrUserData =null; 
94. 
95. } 
96. 
97. finally 
98. 
99. { 
100. 
101. dtCompInfo =null; 
102. 
103. } 
104. 
105. } 
106. 
107. return arrUserData; 
108. 
109. }