聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽 JavaScript涓殑Boolean錛屼綘浜嗚В澶氬皯錛?/font>
聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽聽椹槈妤?/font>聽聽聽聽聽聽2006-10-30
浠婂ぉ鐪嬩簡涓涓?a href="ttp://www.tkk7.com/flyingis">Flyingis鍐欑殑銆?a href="/flyingis/archive/2006/06/13/52484.html?CommentID=78102#Post">ECMAScript 鍩虹銆嬩竴鏂囥傚湪鐪嬪埌
Boolean綾昏繖涓鍧楀唴瀹圭殑鏃跺欙紝闅忔墜鍐欎簡鍑犺浠g爜錛岄棶棰樺嚭鐜頒簡^+^
娉細姝ゆ枃璁ㄨ鐨勬槸JavaScript1.5
榪樻槸鍏堟潵鐪嬩竴孌甸潪甯哥畝鍗曠殑浠g爜
//
code錛?
var
聽x聽
=
聽
false
;聽聽聽
var
聽y聽
=
聽
true
;
//
code錛?
var
聽xObject聽
=
聽
new
聽Boolean(
false
);
var
聽yObject聽
=
聽
new
聽Boolean(
true
);
//
code錛?
var
聽resX聽
=
聽
new
聽Boolean(x);
var
聽resY聽
=
聽
new
聽Boolean(y);
//
code錛?
var
聽resXObject聽
=
聽
new
聽Boolean(xObject);
var
聽resYObject聽
=
聽
new
聽Boolean(yObject);
//
code錛?
alert(
"
resX聽=聽
"
聽
+
聽resX聽
+
聽
"
聽and聽resY聽=聽
"
聽
+
聽resY);
alert(
"
resXObject聽=聽
"
聽
+
聽resXObject聽
+
聽
"
聽and聽resYObject聽=聽
"
聽
+
聽resYObject);
浣犳槑鐧絚ode錛?~4 涔嬮棿鐨勫尯鍒箞錛燂紙浣犱竴瀹氬code錛?鏈涓虹啛鎮夛紝榪欐槸鎴戜滑鏈甯哥敤鐨勶級
浣犵煡閬揷ode錛? 鐨勮緭鍑虹粨鏋滀箞錛燂紙鍙互鍏堟兂鎯籌紝鍦ㄨ繍琛屼唬鐮佺湅緇撴灉錛屽鏋滀笉鏄庣櫧錛屽彲浠ョ戶緇湅涓嬪幓錛?br />
濡傛灉浣犲凡緇忓紑濮嬪ご鏅曚簡錛岄偅灝辨殏鏃朵笉鍘繪兂浜嗭紝鐪嬫垜涓嬮潰鐨勮В閲娿?br />濡傛灉浣犻兘鐭ラ亾浜嗭紙鍝囷紝楂樻墜鍟婏紝鍛靛懙^+^錛夛紝閭f垜榪樻湁涓棶棰橀渶瑕佷綘鐨勮В絳旓紝鍦ㄦ鍏堣阿榪囦簡銆?br />
姝f枃錛?br />JavaScript涓殑Boolean綾誨瀷
1.聽聽聽鎴戜滑鎵鐔熸倝鐨?br />
var x = false;
var y = true;
榪欐槸鎴戜滑澶у閮界啛鎮夌殑錛屾鏃舵垜浠嬌鐢ㄧ殑鏄師濮嬬殑Boolean鍊鹼紙the primitive Boolean values 錛塼rue鍜宖alse
2.聽聽聽鎴戜滑寰堝皯鐢ㄥ埌鐨?/font>
var xObject = new Boolean(false);
var yObject = new Boolean(true);
姝ゆ椂鎴戜滑澹版槑浜嗕竴涓?font color="#0000ff">Boolean瀵硅薄錛孊oolean瀵硅薄鏄Boolean鍊肩殑涓涓皝瑁呫?br />Boolean瀵硅薄錛氫竴涓間負true鎴杅alse鐨凚oolean瀵硅薄銆?br />
鍘熷鐨凚oolean鍊煎拰Boolean瀵硅薄鏄湁鍖哄埆鐨勶紝涓嶈鐩鎬簰娣鋒穯錛屽紩鐢?font color="#0000ff">Core JavaScript 1.5 Reference涓殑涓鍙ヨ瘽錛?font color="#a52a2a">Do not confuse the primitive Boolean values true and false with the true and false values of the Boolean object.
3.聽聽聽鍖哄埆
鍖哄埆錛?錛夛細聽聽聽澹版槑褰㈠紡
鍖哄埆錛?錛夛細聽聽聽鍦ㄦ潯浠惰鍙ワ紙condition statement錛変腑
var聽x聽=聽false;
var聽xObject聽=聽new聽Boolean(false);
if(x)
聽聽聽聽alert("x聽=聽true");
else
聽聽聽聽alert("x聽=聽false");
if(xObject)
聽聽聽聽alert("xObject聽=聽"聽+聽xObject聽+聽",聽but聽in聽the聽condition聽statement,聽the聽xObject聽value聽is聽evaluated聽to聽true");
else
聽聽聽聽alert("xObject聽=聽false");
杈撳嚭緇撴灉錛?br />
x聽=聽false
xObject聽=聽false,聽聽but聽in聽the聽condition聽statement,聽the聽xObject聽value聽is聽evaluated聽to聽true
褰撲竴涓間負false鐨凚oolean瀵硅薄鏀懼埌鏉′歡璇彞褰撲腑鐨勬椂鍊欙紝Boolean瀵硅薄鐨勫間細琚綋浣渢rue鏉ヨ綆楋紝浣嗘槸瀹冩湰韜殑鍊煎茍娌℃湁鏀瑰彉錛屼緷鐒舵槸false銆傚緢鏈夎叮錛屾垜鍙煡閬撶幇璞★紝鍏蜂綋鍘熷洜涓嶆竻妤氾紝涓嶇煡閬撳彂鏄庤呭嚭浜庝粈涔堝湴鑰冭檻銆備絾鏄湪JavaScript1.2鎴栬呮洿鏃╃殑鐗堟湰涓嵈鏈夋墍涓嶅悓錛屽湪鏉′歡璇彞錛坈ondition statement錛変腑錛孊oolean瀵硅薄鐨勮綆楄繑鍥炵殑鏄叾瀵瑰簲鐨勫師濮婤oolean鐨勫箋?br />
鍖哄埆錛?錛夛細鍒濆鍖朆oolean瀵硅薄
澹版槑涓涓狟oolean瀵硅薄錛屽鏋滄垜浠敤涓涓間負false鐨凚oolean瀵硅薄瀵瑰叾榪涜鍒濆鍖栵紝鍒欐柊鐨凚oolean瀵硅薄鐨勫間負true
var聽xObject聽=聽new聽Boolean(false);
var聽resXObject聽=聽new聽Boolean(xObject);
alert("The聽resXObject聽value聽is聽"聽+聽resXObject);
鍘熷鐨凚oolean鍊煎拰Boolean瀵硅薄鍖哄埆濡傛涔嬪ぇ錛屾墍浠ュ垏璁頒簩鑰呭尯鍒紝涓嶈娣鋒穯浣跨敤銆?br />
瀵逛簬code錛? 鐨勮緭鍑虹粨鏋滐紝浣犵幇鍦ㄦ槑鐧芥槸浠涔堝師鍥犱簡鍚с?br />
涓婇潰鐨勪笢涓滄垜涔熸槸浠婂ぉ閬囧埌浜嗛棶棰橈紝鏌ヤ簡涓浜涜祫鏂欐墠鐭ラ亾錛屽鏃犳澧冨晩銆傚彲鏄垜鐨勯棶棰樹緷鐒舵病鏈夎В鍐熾?br />鎴戠殑闂鏄叧浜嶣oolean瀵硅薄鐨勫垵濮嬪寲銆備唬鐮佸涓嬶紝
var聽ob1聽=聽new聽Boolean(false);
var聽ob2聽=聽(ob1&&true);
var聽ob3聽=聽(true&&ob1);
var聽ob4聽=聽Boolean(ob1&&true);
var聽ob5聽=聽Boolean(true&&ob1);
alert("ob2聽=聽"聽+聽ob2聽+聽"聽ob3聽=聽"聽+聽ob3聽+聽"聽ob4聽=聽"聽+聽ob4聽+聽"聽ob5聽=聽"聽+聽ob5);
緇撴灉錛?br />
ob2聽=聽true聽ob3聽=聽false聽ob4聽=聽true聽ob5聽=聽true
鎴戝ob2 鍜?ob3鐨勭粨鏋滀笉澶悊瑙o紝涓轟粈涔堟垜鍙槸鏇存敼浜唎b1鍜宼rue鐨勯『搴忥紝緇撴灉鍘誨畬鍏ㄤ笉鍚屼簡銆傚茍涓斿彲浠ュ彂鐜幫紝緇撴灉鍧囩瓑浜庢搷浣滅鈥?amp;&鈥濆悗闈㈢殑鍊箋?br />
甯屾湜澶у鑳藉憡璇夋垜錛?br />
闂宸茬粡瑙e喅錛?/font>
||鏄繖鏍瘋繍綆楃殑錛氫粠絎竴涓紑濮嬶紝閬囧埌鏈夋剰涔夌殑榪斿洖錛屽惁鍒欒繑鍥炴渶鍚庝竴涓〃杈懼紡錛堟敞鎰忎笉涓瀹氭槸Boolean鍊鹼級錛?
&&鏄繖鏍瘋繍綆楃殑錛氫粠絎竴涓紑濮嬶紝閬囧埌鏃犳剰涔夌殑榪斿洖錛屽惁鍒欒繑鍥炴渶鍚庝竴涓〃杈懼紡錛堟敞鎰忓悓涓婏級錛?
!鏄繖鏍瘋繍綆楃殑錛?/font>瀵硅〃杈懼紡鐨勫煎彇闈烇紙娉ㄦ剰涓嶆槸瀵硅〃杈懼紡錛夈?
浠涔堟槸鏃犳剰涔夊憿錛氬涓嬪叚涓?0,null,undefined,"",false,NaN銆傞櫎姝わ紝瑙嗕負鏈夋剰涔夈?
new Boolean(),new Boolean(false)鏄悓涓涓笢瑗匡紝鐢變簬瀹冩槸涓涓璞★紝鏁呮槸鏈夋剰涔夌殑錛屼絾鍏跺間負false錛屾墍浠ワ紝鍙互鐪嬩負鈥滄湁鎰忎箟鐨刦alse鈥濓紝鎵浠ョ粨鏋滀負鏈鍚庝竴涓〃杈懼紡鐨勫箋?
璋㈣阿
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