JS regular expression applications

　　Determine whether the string contains Chinese characters:　　　　

var pattern = /.*[\u4e00-\u9fa5]+.*$/;
var str = "asd按时";
console.log(pattern.test(str));

　　Determine whether the string are all in English:

var pattern = new RegExp("^[a-zA-Z]+$");
var str = "asd按时";
console.log(pattern.test(str));

　　Determining whether the character string contains a +, -, *, / operator:

var pattern = /[+*/-]/;
var str = "asd按时";
console.log(pattern.test(str));

　　

　　Regular expression builder Online: http://tools.jb51.net/regex/create_reg