当提示 "Did you find anything..." 运行时，提示文本包含 "false" 而不是实际文本

Question

    var route = 2; var name = prompt("'What is your name soldier?'");

 if(route === 2) {
  if (prompt ("Well,. Did you find anything unusual out on your patrol? (Lie or truth?)".length === 3)) {
  alert("'No sir, nothing unusual.' you say.")
 }
 else
  alert("'Well, I did find a warehouse sir. It was emitting a strange sound, but I thought nothing of it.' you say")
 }

Answer 1

这一行有问题：

if (prompt ("Well,. Did you find anything unusual out on your patrol? (Lie or truth?)".length === 3)) {

它使用布尔值作为 prompt() 的值 - 例如if (prompt(string length ===3) {... 因为属性 .length is being accessed on the string passed to prompt()，而不是提示中的 return 值.

要检查用户输入的字符串的长度，请在访问 .length 属性之前移动括号之一，如下所示：

if (prompt ("Well,. Did you find anything unusual out on your patrol? (Lie or truth?)").length === 3) {

在此代码段中尝试一下（单击标有 运行代码段 的按钮）：

 var route = 2; var name = prompt("'What is your name soldier?'");

 if(route === 2) {
  if (prompt ("Well,. Did you find anything unusual out on your patrol? (Lie or truth?)").length === 3) {
  alert("'No sir, nothing unusual.' you say.")
 }
 else
  alert("'Well, I did find a warehouse sir. It was emitting a strange sound, but I thought nothing of it.' you say")
 }

当提示 "Did you find anything..." 运行时，提示文本包含 "false" 而不是实际文本

When the prompt "Did you find anything..." runs, the prompt text contains "false" instead of actual text

javascript

prompt