瀹胯垗绠＄悊绯荤粺绛旇京闂鎬荤粨

Posted 2020-11-28

鏍囩锛?a href='http://www.mamicode.com/so/1/max' title='max'>max   data   绠＄悊   tor   return   鎶ラ敊   鑷畾涔夌被   

1.绗竴琛寀sing System鏄粈涔堟剰鎬濓紵
绛旓細using system;鍦–#涓寚鐨勬槸鍛藉悕绌洪棿鐨勬剰鎬濓紝寮曞叆鍛藉悕绌洪棿鐩稿綋浜嶫ava閲岀殑import java.util寮曞叆鍖呯殑浣滅敤锛屽紩鍏ュ懡鍚嶇┖闂达紝浣犲氨鍙互浣跨敤鍏朵腑鐨勫彉閲忓悕鍜屽嚱鏁般€?br/>姣斿鐢⊿tringBuilder绫伙紝灏变笉鐢⊿ystem.Text.StringBuilder builder = new System.Text.StringBuilder()浜嗐€?/p>

2.namespace浠ュ強鍚庨潰鐨勬槸浠€涔堟剰鎬濓紵
绛旓細 鍛藉悕绌洪棿锛岀浉褰撲簬namespace鐩稿綋浜巜indows鎿嶄綔绯荤粺涓殑鏂囦欢澶广€傗€滈」鐩悕.鏂囦欢澶瑰悕鈥濓紝鐢ㄤ簬缁嗗垎鏂囦欢銆?/p>

3.Public涓巔rivate鐨勫尯鍒強鍔熻兘
绛旓細private鏄畬鍏ㄧ鏈夌殑锛屽彧鏈夊湪绫昏嚜宸遍噷闈㈠彲浠ヨ皟鐢紝鍦ㄧ被鐨勫閮ㄥ拰瀛愮被閮戒笉鑳借皟鐢紝瀛愮被涔熶笉鑳界户鎵跨埗绫荤殑private鐨勫睘鎬у拰鏂规硶銆?br/>public瀵逛换浣曠被鍜屾垚鍛橀兘瀹屽叏鍏紑锛屾棤闄愬埗璁块棶銆?/p>

4.@绗﹀彿鐨勪綔鐢?br/>绛旓細1.蹇界暐杞箟瀛楃锛?.璁╁瓧绗︿覆璺ㄨ锛?.鍦ㄦ爣璇嗙涓殑鐢ㄦ硶锛欳#鏄笉鍏佽鍏抽敭瀛椾綔涓烘爣璇嗙(绫诲悕銆佸彉閲忓悕銆佹柟娉曞悕銆佽〃绌洪棿鍚嶇瓑)浣跨敤鐨勶紝浣嗗鏋滃姞涓夽涔嬪悗灏卞彲浠ヤ簡銆?/p>

5.瑙ｉ噴涓€涓媎elete鏂规硶涓姤閿欐満鍒讹紝杩愯娴佺▼
绛旓細1銆佸皢棰勮鍙兘寮曞彂寮傚父鐨勪唬鐮佸寘鍚湪try璇彞鍧椾腑銆?
2銆佸鏋滃彂鐢熶簡寮傚父锛屽垯杞叆catch鐨勬墽琛屻€?br/>3銆乫inally鍙互娌℃湁锛屼篃鍙互鍙湁涓€涓€傛棤璁烘湁娌℃湁鍙戠敓寮傚父锛屽畠鎬讳細鍦ㄨ繖涓紓甯稿鐞嗙粨鏋勭殑鏈€鍚庤繍琛屻€傚嵆浣夸綘鍦╰ry鍧楀唴鐢╮eturn杩斿洖浜嗭紝鍦ㄨ繑鍥炲墠锛宖inally鎬绘槸瑕佹墽琛岋紝杩欎互渚胯浣犳湁鏈轰細鑳藉鍦ㄥ紓甯稿鐞嗘渶鍚庡仛涓€浜涙竻鐞嗗伐浣溿€傚鍏抽棴鏁版嵁搴撹繛鎺ョ瓑绛夈€傦紙濡傛灉娌℃湁catch璇彞鍧楋紝閭ｄ箞finally鍧楀氨鏄繀椤荤殑銆傦級

6.瑙ｉ噴涓€涓嬪崰浣嶇{0}
绛旓細鎺ユ敹绗竴涓紶閫掕繃鏉ョ殑鍙傛暟

7.瑙ｉ噴涓€涓嬪弬鏁板垪琛ㄦ涓殑鍐呭
绛旓細澹版槑涓€涓彉閲忔垨绫伙紝鎺ユ敹鐣岄潰浼犻€掓潵鐨勫弬鏁?/p>

8.瑙ｉ噴涓€涓媠ql璇彞
绛旓細鏌ヨx琛ㄤ腑鐨刟,b鍒?/p>

9.Datatable鏄粈涔堬紵
绛旓細DataTable鏄竴涓复鏃朵繚瀛樻暟鎹殑缃戞牸铏氭嫙琛?琛ㄧず鍐呭瓨涓暟鎹殑涓€涓〃銆?锛屽瓨鏀句粠鏁版嵁搴撴煡璇㈠埌鐨勬暟鎹€?/p>

10.String.format瑙ｉ噴涓€涓?br/>绛旓細string.format() 鏍煎紡鍖栬鏄庣锛屽皢鎸囧畾鐨?String绫诲瀷鐨勬暟鎹腑鐨勬瘡涓牸寮忛」鏇挎崲涓虹浉搴斿璞＄殑鍊肩殑鏂囨湰绛夋晥椤广€?/p>

11.Return鍦ㄦ柟娉曚腑鐨勪綔鐢?br/>绛旓細鍦ㄦ湁杩斿洖鍊肩殑鏂规硶涓殑浣滅敤锛歳eturn鍚庨潰璺熻繑鍥炲€硷紝杩斿洖鍊肩被鍨嬭涓庢柟娉曡繑鍥炲€肩被鍨嬬浉鍚岋紝濡傗€減ublic int intt()鈥濈殑鏂规硶杩斿洖鍊肩被鍨嬩负Int锛屽垯return鍚庤窡鐨勮繑鍥炲€肩被鍨嬩篃蹇呴』涓篿nt銆俁eturn灏嗚繑鍥炲€艰祴缁欐柟娉曪紝鍙互鐩存帴浠庢柟娉曚腑璋冪敤鍊笺€?br/>鍦ㄦ棤杩斿洖鍊肩殑鏂规硶涓殑浣滅敤锛氱粨鏉熸柟娉曠殑杩愯銆?/p>

12.return DBhelper.query(sql).Rows.Count;瑙ｉ噴涓€涓?br/>绛旓細return 灏咲BHelper.query(sql)涓璂ataTable绫诲瀷鐨勬暟鎹殑鎬昏鏁拌繑鍥炵粰绫诲瀷涓篒nt鐨勬柟娉曘€?/p>

13.public partial class Form1 : Form 鏄粈涔堟剰鎬濓紵
绛旓細绐椾綋Form1缁ф壙绯荤粺涓负Form鐨勭獥浣撴牸寮忋€?/p>

14.private void btnSubmit_Click(object sender, EventArgs e)瑙ｉ噴涓€涓嬶紙锛夐噷鐨?br/>绛旓細绯荤粺鍙傛暟

15.This 鏄寚浠€涔堬紵
绛旓細杩欎釜绐椾綋

16.this.Close();瑙ｉ噴涓€涓?br/>绛旓細鍏抽棴鏈獥浣?/p>

17.private void StuChargeForm_Load(object sender, EventArgs e)瑙ｉ噴涓€涓嬫槸鍟ヤ簨浠?br/>绛旓細绐椾綋鍔犺浇浜嬩欢锛屽湪绗竴娆℃樉绀虹獥浣撳墠鍙戠敓銆?/p>

18.DataSource琛ㄧず浠€涔堬紵
绛旓細鏁版嵁婧?/p>

19.public void flush() void琛ㄧず浠€涔堬紵
绛旓細void琛ㄧず璇ユ柟娉曟病鏈夎繑鍥炲€笺€?/p>

20.Static琛ㄧず浠€涔堬紵鏈変粈涔堜綔鐢紵
绛旓細闈欐€佷慨楗扮锛屽湪鏂规硶锛堝嚱鏁帮級鍓嶇敤static淇グ锛岃〃绀烘鏂规硶涓烘墍鍦ㄧ被鎴栨墍鍦ㄨ嚜瀹氫箟绫绘墍鏈夛紝鑰屼笉鏄繖涓被鐨勫疄渚嬫墍鏈夈€傚彲浠ラ€氳繃绫荤洿鎺ヨ皟鐢ㄩ潤鎬佹柟娉曪紝浣嗕笉鍙互閫氳繃杩欎釜绫荤殑瀹炰緥鏉ヨ皟鐢ㄥ叾涓殑闈欐€佹柟娉曪紝鍥犱负閫氳繃瀹炰綋绫昏皟鐢ㄥ叾涓殑闈欐€佹柟娉曟椂锛屽璞″彲鑳戒笉瀛樺湪銆傞潤鎬佹柟娉曚笉鑳借閲嶅啓锛屽彧鑳借閲嶈浇锛屽洜涓洪潤鎬佹柟娉曚笉灞炰簬绫荤殑瀹炰緥瀵硅薄銆?/p>

21.InitializeComponent();鏈変粈涔堜綔鐢ㄣ€侊紵
绛旓細鍒濆鍖栫獥浣撴帶浠?/p>

22.if (this.cboFlag.Text == "鍦ㄨ亴") t.flag = "1";
else if (this.cboFlag.Text == "绂昏亴") t.flag = "2";
else if (this.cboFlag.Text == "浼戝亣") t.flag = "3";瑙ｉ噴涓€涓媔f鍒ゆ柇鐨勮繍琛屾祦绋?br/>绛旓細鐣?/p>

23.this.lblPage.Text = "褰撳墠锛?quot; + page.nowPage + "椤? 鍏憋細" + page.getTotalPage() + "椤? 鎬昏锛?quot; + page.count + "鏉?quot;; 涓殑+琛ㄧず浠€涔堬紵
绛旓細鏄剧ず鍒嗛〉涓殑褰撳墠椤靛拰鎬婚〉鏁?/p>

24.this.cboFlag.Text = "鍦ㄨ亴"; cboFlag鏄粈涔堟帶浠讹紵
绛旓細涓嬫媺妗?/p>

25.dgvTeacher.SelectedRows[0].Cells["teachid"].Value.ToString()瑙ｉ噴涓€涓嬭繖涓€琛?br/>绛旓細dgv涓€変腑鐨勮鐨勭涓€琛屼腑鐨則eachid鍒椾腑鐨勫€艰浆鍖栦负瀛楃鍒涚被鍨?/p>

26.=涓?=鐨勫尯鍒?br/>绛旓細=鏄祴鍊硷紝==鏄垽鏂?/p>

27.int.Parse鏄紕鍟ュ槥锛?br/>绛旓細灏嗭紙锛夐噷鐨勫€艰鎹负int绫诲瀷

28.this.cboTeacher.Items.Add("鍏ㄩ儴");杩欏張鏄紕鍟ュ槥锛?br/>绛旓細寰€杩欎釜绐椾綋涓殑浼犳挱teacher涓嬫媺妗嗙殑閫夐」涓坊鍔犱竴椤光€樺叏閮ㄢ€?/p>

29.dt.Rows[0]["stuname"].ToString();瑙ｉ噴杩欎竴琛?br/>绛旓細鎶奷tz涓殑绗竴琛岀殑stuname鍒楃殑鍊艰鎹负瀛楃鍒?/p>

30.left join涓巌nner join涓巖ight join鏈変粈涔堝尯鍒紵
绛旓細left join(宸﹁仈鎺? 杩斿洖鍖呮嫭宸﹁〃涓殑鎵€鏈夎褰曞拰鍙宠〃涓仈缁撳瓧娈电浉绛夌殑璁板綍锛?br/>inner join(绛夊€艰繛鎺? 鍙繑鍥炰袱涓〃涓仈缁撳瓧娈电浉绛夌殑琛岋紱
right join(鍙宠仈鎺? 杩斿洖鍖呮嫭鍙宠〃涓殑鎵€鏈夎褰曞拰宸﹁〃涓仈缁撳瓧娈电浉绛夌殑璁板綍銆?/p>

31.d.dormNum like 鈥?{6}%鈥樿В閲婁竴涓? %-閫氶厤绗?br/>绛旓細妯＄硦鏌ヨ {6}琛ㄧず鎺ュ彈浼犺繃鏉ョ殑绗竷涓弬鏁帮紝%-鏇夸唬涓€涓垨澶氫釜瀛楃銆?/p>

32.limit {0},{1}瑙ｉ噴涓€涓嬪崰浣嶇0鍜?鐨勪綔鐢?br/>绛旓細{0} 琛ㄧず浠庣鍑犳潯鏁版嵁寮€濮嬫樉绀猴紝{1}琛ㄧず鏄剧ず姣忛〉鍑犳潯鏁版嵁

33.璇翠竴涓嬫湁鍑犱釜鑱氬悎鍑芥暟
绛旓細max锛宮in,count,avg锛宻um

34.鍏ぇ鍩烘湰绫诲瀷
绛攂yte,short,int,long,float,double,bool,char

35.鍒嗗埆瑙ｉ噴涓€涓婼ql璇彞涓殑and鍜宱r
绛旓細鐣?/p>

36.涓庢垨闈炵殑浼樺厛绾?br/>闈?gt;涓?gt;鎴?/p>

37.Displaymember鍜寁aluemember鐨勫惈涔?br/>绛旓細displaymember缁戝畾闇€鏄剧ず瀛楁锛寁aluemember缁戝畾瀵瑰簲displaymember鐨勫€笺€傚悓閿€煎鐩镐技銆?/p>

38.绐椾綋鍏抽棴鍚庝负浠€涔堣new涓€涓柊鐨勫璞?br/>绛旓細鍥犱负鍒涘缓浜咶actory绫伙紝鎵€鏈夌殑绐椾綋閮芥槸浠嶧actory绫讳腑璋冪敤鐨勶紝涓擣actory绫讳腑鐨勭獥浣撻兘涓洪潤鎬侊紝淇濊瘉浜嗙獥浣撶殑鍞竴鎬с€傚綋绐椾綋鍏抽棴鏃讹紝Factory绫讳腑鐨勭獥浣撳疄渚嬪璞＄殑鍊煎彉鎴怤ull锛屽湪涓嬫浠嶧actory绫讳腑璋冪敤绐椾綋鏃讹紝浼氬脊鍑篍rror锛屽洜姝ゅ湪绐椾綋鍏抽棴鏃讹紝瑕乶ew涓€涓柊鐨勭獥浣撶粰瀹炰緥瀵硅薄鐣欎綔澶囩敤銆?/p>

39.if (i == j) ()涓繑鍥炰粈涔堬紵
绛旓細true||false

40.this.dgvstudent.SelectedRows.Count杩欐槸骞插暐鍢烇紵
绛旓細缁熻涓€鍏卞灏戣

41.Student s = new Student();涓轰粈涔堣new涓€涓柊鐨勫璞?br/>绛旓細鐢ㄦ潵淇濆瓨鐣岄潰涓婄敤鎴疯緭鍏ョ殑鏁版嵁鎴栨帴鏀舵暟鎹簱鏌ヨ鍑烘潵鐨勬暟鎹€?/p>

42.鍒犻櫎闇€瑕佽皟鐢―Bhelper涓殑鍝釜鏂规硶锛屼负浠€涔堬紵
绛旓細闈炴煡璇㈡柟娉曪紝闈炴煡璇㈡柟娉曡礋璐ｈ繛鎺ラ潪鏌ヨ璇彞杩炴帴鏁版嵁搴?/p>

43.涓轰粈涔堜娇鐢?=锛熷畠鏈変粈涔堜綔鐢紵
绛旓細璁?宸﹁竟鐨勫姞涓婂彸杈圭殑鍊艰绠楃粨鏋滆祴鍊肩粰=宸﹁竟鐨勫€硷紝缁熻鏀惰垂鎬婚噾棰?/p>

44.if (this.rdoStudent.Checked)浼氳繑鍥炰粈涔堬紵
绛旓細true||false

45.Page++ 涓殑++鏄粈涔堟剰鎬濓紵
绛旓細閫掑1
46.Mdiparent鏈変粈涔堜綔鐢紵
绛旓細璁剧疆绐椾綋鐨勭埗绐椾綋

47.Application.Exit锛堬級涓巘his.close鏈変粈涔堝尯鍒紵
绛旓細Application.Exit()鍏抽棴鎵€鏈夊簲鐢ㄧ▼搴忕獥鍙ｏ紝缁堟绋嬪簭杩愯锛汧orm.Close 鏂规硶鍏抽棴绐椾綋銆?/p>

48.Order by 涓?group by鐨勫尯鍒紵Asc鍜宒esc鐨勫尯鍒紵
绛旓細groud by 鍏锋湁鍒嗙粍鍚堝苟琛岀殑浣滅敤銆傚皢groud by 鍚庨潰鐨勫垪鎸夎鍊肩浉鍚屽垝褰掑悎骞舵垚涓€琛岋紝杩涜鐩稿悓鏁版嵁鐨勭粺璁″伐浣滐紝涓€鑸粨鍚堣仛鍚堝嚱鏁颁娇鐢ㄣ€?br/>Order by 鍏锋湁鎸夋潯浠舵帓搴忕殑浣滅敤銆侫sc鏄搴忥紝order by榛樿涓烘搴忔帓搴忥紝desc涓哄€掑簭銆?br/>group by 姣攐rder by鍏堟墽琛岋紝order by涓嶄細瀵筭roup by 鍐呴儴杩涜鎺掑簭锛屽鏋済roup by鍚庡彧鏈変竴鏉¤褰曪紝閭ｄ箞order by 灏嗘棤鏁堛€?/p>

49.Textchanged鏄敤鏉ュ共鍟ュ槥锛?br/>绛旓細鏂囨湰鏀瑰彉鏃跺彂鐢熶簨浠?/p>

50.Indexof鏄紕鍟ュ槥锛熻繑鍥炰釜鍟ワ紵
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