Question

我在JavaScript中做错了什么？如果用户忘记输入任何HTML表单字段，我想显示错误消息。我想为名称，电子邮件和电话号码字段创建一条错误消息。即使用户输入了他们的名字，我也希望余数为2或余数为1的错误消息，或者没有错误消息。我在下面附上了我的JavaScript代码。感谢那些帮助的人。

function validateForm() {
  var ret = true;
  var name = document.forms["contactform"]["name"].value;
  if (name == "") {
    document.getElementById('error').innerHTML = "Please enter your name";
    ret = false;
  }
  var email = document.forms["contactform"]["email"].value;
  if (email == "") {
    document.getElementById('erroremail').innerHTML = "Please enter your email";
    ret = false;
  }

  var phone = document.forms["contactform"]["phone"].value;
  if (phone == "") {
    document.getElementById('errorphone').innerHTML = "Please enter your phone";
    ret = false;
  }
  return ret;
}

Answer 1

创建一个名为：

的变量

var fieldsInError = "";

然后在每次检查的验证中，如果验证失败，请添加字段：

fieldsInError += "name," (or whatever the field is)

然后在函数结束时更新您的错误字段，例如：

document.getElementById('error').innerHTML = "Please enter " + fieldsInError.substring(0, fieldsInError.length-1);

所以你的功能看起来像这样：

function validateForm() {
  var fieldsInError = "";
  var name = document.forms["contactform"]["name"].value;
  if (name == "") {
    fieldsInError += "name,"
  }
  var email = document.forms["contactform"]["email"].value;
  if (email == "") {
    fieldsInError += "email,"
  }

  var phone = document.forms["contactform"]["phone"].value;
  if (phone == "") {
    fieldsInError += "phone,"
  }

  if(fieldsInError != ""){
    document.getElementById('error').innerHTML = "Please enter " + fieldsInError.substring(0, fieldsInError.length-1);
    return false;
  } else {
    return true;
  }
}

Answer 2

如果您希望为每个输入单独显示错误，则只需添加else空innerHTML。

这样的事情：

var name = document.forms["contactform"]["name"].value;
var nameError = document.getElementById('error');
if (name == "") {
  nameError.innerHTML = "Please enter your name";
  ret = false;
} else {
  nameError.innerHTML = "";
}

此处的完整示例：https://jsfiddle.net/1h1tkh7y/

JavaScript显示多个错误消息表单提交？

2 个答案: