字符串(String)
1.聲明
varmyString =newString(“Every good boy does fine.”);
varmyString = “Every good boy does fine.”;
2.字符串連接
varmyString = “Every ” + “good boy ” + “does fine.”;
varmyString = “Every “; myString += “good boy does fine.”;
3.截取字符串
//截取第 6 位開始的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substring(6);//結果: “good boy does fine.”
//截取第 0 位開始至第 10 位為止的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substring(0,10);//結果: “Every good”
//截取從第 11 位到倒數(shù)第 6 位為止的字符
varmyString = “Every good boy does fine.”;
varsection = myString.slice(11,-6);//結果: “boy does”
//從第 6 位開始截取長度為 4 的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substr(6,4);//結果: “good”
4.轉換大小寫
varmyString = “Hello”;
varlcString = myString.toLowerCase();//結果: “hello”
varucString = myString.toUpperCase();//結果: “HELLO”
5.字符串比較
varaString = “Hello!”;
varbString =newString(“Hello!”);
if( aString == “Hello!” ){ }//結果: true
if( aString == bString ){ }//結果: true
if( aString === bString ){ }//結果: false (兩個對象不同,盡管它們的值相同)
6.檢索字符串
varmyString = “hello everybody.”;
// 如果檢索不到會返回-1,檢索到的話返回在該串中的起始位置
if( myString.indexOf(“every”) >-1){ }//結果: true
7.查找替換字符串
varmyString = “I is your father.”;
varresult = myString.replace(“is”,”am”);//結果: “I am your father.”
8.特殊字符:
\b : 后退符 \t : 水平制表符
\n : 換行符 \v : 垂直制表符
\f : 分頁符 \r : 回車符
\” : 雙引號 \’ : 單引號
\\ : 反斜桿
9.將字符轉換成Unicode編碼
varmyString = “hello”;
varcode = myString.charCodeAt(3);//返回”l”的Unicode編碼(整型)
varchar =String.fromCharCode(66);//返回Unicode為66的字符
10.將字符串轉換成URL編碼
varmyString = “hello all”;
varcode =encodeURI(myString);//結果: “hello%20all”
varstr =decodeURI(code);//結果: “hello all”
//相應的還有: encodeURIComponent() decodeURIComponent()
