switch哪里错了呢
var in2 = parseInt(document.getElementById("txt2").value);
var in3 = document.getElementById("select").value ;
var result = 0;
switch(in3){
case '+' : result = in1 + in2;
break;
case '-' : result = in1 - in2;
break;
case '*' : result = in1 * in2;
break;
case '/' : result = in1 / in2;
break;
}
这里的switch语句哪里出了问题啊