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var myStr = "Hello, String!";
æ们å¨ä¸é¢èæ¬å建äºå符串ï¼ä½æ¬è´¨ä¸ï¼å®ä»¬å¹¶ä¸æ¯çæ£çå符串对象ï¼åç¡®å°è¯´ï¼å®ä»¬æ¯å符串类åçå¼ãè¦å建ä¸ä¸ªå符串对象ï¼å¯ä½¿ç¨å¦ä¸è¯å¥ï¼var strObj = new String("Hello, String!");
使ç¨typeofè¿ç®ç¬¦æ¥çä¼åç°ï¼ä¸é¢çmyStrç±»å为stringï¼èstrObjç±»å为objectã
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var longString = "One piece " + "plus one more piece.";
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var result = "";
result += "My name is Anders"
result += " and my age is 25";
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var confirmString = "You did not enter a response to the last " +
"question./n/nSubmit form anyway?";
var confirmValue = confirm(confirmString);
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åµä¸ï¼å¦æå°è¿æ®µææ¬ä½ä¸ºHTMLå
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var htmlString = "First line of string.<br>Second line of string.";
document.write(htmlString);
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string.concat(value1, value2, ...)
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substring()çååä¸ºï¼ string.substring(from, to)
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var fullString = "Every dog has his day.";
var section = fullString.substring(0, 4); // section is "Ever".
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var city = "ShanGHai";
city = city.toLowerCase(); // city is "shanghai" now.
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var name = document.form1.txtUserName.value.toLowerCase();
if(name == "urname")
{
// statements go here.
}
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var strA = "i love you!";
var strB = new String("i love you!");
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if(document.form1.txtAge.value == someNumericVar) { ... }
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var strings; // è¦æåºçå符串æ°ç»ï¼å设已ç»å¾å°åå§å
strings.sort(function(a,b) { return a.localeCompare(b) }); // è°ç¨sort()æ¹æ³è¿è¡æåº
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strObj.indexOf(subString[, startIndex])
strObj为è¦è¿è¡å¤æçå符串ï¼subString为è¦å¨strObjæ¥æ¾çåå符串ï¼startIndexæ¯å¯éçï¼è¡¨ç¤ºæ¥æ¾çå¼å§ä½ç½®(åºäº0çç´¢å¼)ï¼å¦æstartIndexçç¥ï¼åä»strObjå¼å§å¤æ¥æ¾ï¼å¦æstartIndexå°äº0ï¼åä»0å¼å§ï¼å¦æstartIndex大äºæ大索å¼ï¼åä»æ大索å¼å¤å¼å§ã
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{
// å¦æå
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}
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function countInstances(mainStr, subStr)
{
var count = 0;
var offset = 0;
do
{
offset = mainStr.indexOf(subStr, offset);
if(offset != -1)
{
count++;
offset += subStr.length;
}
}while(offset != -1)
return count;
}
String对象æä¸ä¸ªä¸indexOf()对åºçæ¹æ³ï¼lastIndexOf()ï¼
strObj.lastIndexOf(substring[, startindex])
strObj为è¦è¿è¡å¤æçå符串ï¼subString为è¦å¨strObjæ¥æ¾çåå符串ï¼startIndexæ¯å¯éçï¼è¡¨ç¤ºæ¥æ¾çå¼å§ä½ç½®(åºäº0çç´¢å¼)ï¼å¦æstartIndexçç¥ï¼åä»strObjæ«å°¾å¤æ¥æ¾ï¼å¦æstartIndexå°äº0ï¼åä»0å¼å§ï¼å¦æstartIndex大äºæ大索å¼ï¼åä»æ大索å¼å¤å¼å§ã该æ¹æ³èªå³åå·¦æ¥æ¾ï¼è¿åsubStringå¨strObjä¸æååºç°çä½ç½®ï¼å¦æ没ææ¾å°ï¼è¿å-1ã
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