字符串(String)
1.声明
varmyString =newString(“Every good boy does fine.”);
varmyString = “Every good boy does fine.”;
2.字符串连接
varmyString = “Every ” + “good boy ” + “does fine.”;
varmyString = “Every “; myString += “good boy does fine.”;
3.截取字符串
//截取第 6 位开始的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substring(6);//结果: “good boy does fine.”
//截取第 0 位开始至第 10 位为止的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substring(0,10);//结果: “Every good”
//截取从第 11 位到倒数第 6 位为止的字符
varmyString = “Every good boy does fine.”;
varsection = myString.slice(11,-6);//结果: “boy does”
//从第 6 位开始截取长度为 4 的字符
varmyString = “Every good boy does fine.”;
varsection = myString.substr(6,4);//结果: “good”
4.转换大小写
varmyString = “Hello”;
varlcString = myString.toLowerCase();//结果: “hello”
varucString = myString.toUpperCase();//结果: “HELLO”
5.字符串比较
varaString = “Hello!”;
varbString =newString(“Hello!”);
if( aString == “Hello!” ){ }//结果: true
if( aString == bString ){ }//结果: true
if( aString === bString ){ }//结果: false (两个对象不同,尽管它们的值相同)
6.检索字符串
varmyString = “hello everybody.”;
// 如果检索不到会返回-1,检索到的话返回在该串中的起始位置
if( myString.indexOf(“every”) >-1){ }//结果: true
7.查找替换字符串
varmyString = “I is your father.”;
varresult = myString.replace(“is”,”am”);//结果: “I am your father.”
8.特殊字符:
\b : 后退符 \t : 水平制表符
\n : 换行符 \v : 垂直制表符
\f : 分页符 \r : 回车符
\” : 双引号 \’ : 单引号
\\ : 反斜杆
9.将字符转换成Unicode编码
varmyString = “hello”;
varcode = myString.charCodeAt(3);//返回”l”的Unicode编码(整型)
varchar =String.fromCharCode(66);//返回Unicode为66的字符
10.将字符串转换成URL编码
varmyString = “hello all”;
varcode =encodeURI(myString);//结果: “hello%20all”
varstr =decodeURI(code);//结果: “hello all”
//相应的还有: encodeURIComponent() decodeURIComponent()
