Question

我使用以下JavaScript在输入字段中添加小数：

<INPUT NAME="display" ID="disp" VALUE="0" SIZE="28" MAXLENGTH="25"/>
<button TYPE="button" ID="button-1" VALUE="1">1</button>
<button TYPE="button" ID="button-2" VALUE="2">2</button>
<button TYPE="button" ID="button-3" VALUE="3">3</button>
<button TYPE="button" ID="button-4" VALUE="4">4</button>
<button TYPE="button" ID="button-5" VALUE="5">5</button>
<button TYPE="button" ID="button-6" VALUE="6">6</button>
<button TYPE="button" ID="button-7" VALUE="7">7</button>
<button TYPE="button" ID="button-8" VALUE="8">8</button>
<button TYPE="button" ID="button-9" VALUE="9">9</button>
<button TYPE="button" ID="button-0" VALUE="0">0</button>
<button TYPE="button" ID="button-dot" VALUE=".">.</button>

使用HTML标记：

#button-dot

当用户在任意数字键之前按下date,color,id,zip,weight,height,locale 11/25/2013,Blue,122468,1417464,3546600,254,7键时，小数点会出现在其左边没有零的情况下，我希望是这种情况。那么有没有办法改变这个代码，以便当用户输入小数点作为第一个键时，小数点左边会出现零？

Answer 1

试试这个处理程序：

<击>

$('#button-dot').click(function(){
    var txt = disp.val().replace(/\./g, '');
    if(!txt)
        txt = '0';
    txt += '.';
    disp.val(txt);
});

<击>

＆＃13;

$(function() {

  var disp = $('#disp');

  //all buttons except for last button `dot`
  $('[id^=button-]').slice(0, -1).click(function() {
    var txt = disp.val();
    if('0' === txt) { //modified condition
      txt = '';
    }
    disp.val(txt + this.value);
  });

  $('#button-dot').click(function() {
    var txt = disp.val().replace(/\./g, ''); //replace all previous dots
    if (!txt)
      txt = '0';
    disp.val(txt + '.');
  });

});

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<INPUT NAME="display" ID="disp" VALUE="0" SIZE="28" MAXLENGTH="25" />
<button TYPE="button" ID="button-1" VALUE="1">1</button>
<button TYPE="button" ID="button-2" VALUE="2">2</button>
<button TYPE="button" ID="button-3" VALUE="3">3</button>
<button TYPE="button" ID="button-4" VALUE="4">4</button>
<button TYPE="button" ID="button-5" VALUE="5">5</button>
<button TYPE="button" ID="button-6" VALUE="6">6</button>
<button TYPE="button" ID="button-7" VALUE="7">7</button>
<button TYPE="button" ID="button-8" VALUE="8">8</button>
<button TYPE="button" ID="button-9" VALUE="9">9</button>
<button TYPE="button" ID="button-0" VALUE="0">0</button>
<button TYPE="button" ID="button-dot" VALUE=".">.</button>

＆＃13;

Answer 2

不完全确定您想要什么，但此代码将使用0.替换点或零或空输入：

function addChar(input, character) {
  if (input.value == '' || input.value == '.' || input.value == "0"){
    input.value = "0" + character}
  else{
    input.value += character}
  };

$('#button-dot').click(function() {
  addChar($('input').get(0), '.');
  });

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input id="i" />
<button id="button-dot">.</button>

添加字符函数需要在小数点前加0

2 个答案: