javascript如果elseif不工作

Question

救命!if/elseif/else代码块不起作用!当代码到达提示"你会做什么？" 无论你键入什么,你都会收到所有警报.当您键入不在if块中的命令时,它应该显示为空白,如果您输入了R,L或M,则会显示警告.键入F应该不会给出警报.

while (Room = 1) {
    var Choice = prompt ("What will you do?");
    if (Turn = "Start");
    {
        if (Choice = "F");
    {
        Turn = "1";
    }
    else if (Choice = "R");
    {
        alert ("You cannot do that...");
    }
    else if (Choice = "L");
    {
        alert ("You cannot do that...");
    }
    else if (Choice = "M");
    {
        alert ("    1"+'\n'+"    1" + '\n' + "221" + '\n' + "    X");
    }
    else 
    {
        alert ("You cannot do that...")
    }
}

Answer 1

用==而不是=.单个等于是变量赋值,并根据赋值的结果进行求值.==用于相等测试.