JS判断字符串是否为空或是否全为空格

 1 var test = " ??\n ??"; 2 //var test = " ?????"; 3 if(test.match(/^\s+$/)){ 4 ????console.log("all space or \\n") 5 } 6 if(test.match(/^[ ]+$/)){ 7 ????console.log("all space") 8 } 9 if(test.match(/^[ ]*$/)){10 ????console.log("all space or empty")11 }12 if(test.match(/^\s*$/)){13 ????console.log("all space or \\n or empty")14 }