JS判断字符串是否为空或是否全为空格

var test = " ?????";//为空或全部为空格if (test.match(/^[ ]*$/)) { ???????console.log("all space or empty");}

var test = " ??\n ??";//var test = " ?????";if(test.match(/^\s+$/)){ ???console.log("all space or \\n")}if(test.match(/^[ ]+$/)){ ???console.log("all space")}if(test.match(/^[ ]*$/)){ ???console.log("all space or empty")}//空|空格|换行if(test.match(/^\s*$/)){ ???console.log("all space or \\n or empty")}