如何在文本字段中模拟退格动作?

所以我猜你不是想把焦点放在文本输入上删除它。

你可以尝试几种方法。首先,获取输入的当前内容并删除最后一个字符,然后将修改后的字符串放回原处。例如(此代码应该有效):

var txt = $('#myinputtextbox');
txt.val(txt.val().slice(0, -1));

另一种方法是使用JS模拟被点击的退格字符键。您需要将焦点放在输入上,将光标移动到行尾,然后触发字符。

这似乎在Safari(可能还有Firefox)中有效,但我还没有在IE中测试过它:

  function backspaceAtCursor(id)
  {
    var field = document.getElementById(id);

    if(field.selectionStart)
    {
      var startPos = field.selectionStart;
      var endPos = field.selectionEnd;

      if(field.selectionStart == field.selectionEnd)
      {
        field.value = field.value.substring(0, startPos - 1) + field.value.substring(endPos, field.value.length);

        field.focus(); 
        field.setSelectionRange(startPos - 1, startPos - 1); 
      }
      else
      {
        field.value = field.value.substring(0, startPos) + field.value.substring(endPos, field.value.length);

        field.focus(); 
        field.setSelectionRange(startPos, startPos); 
      }
    }
  }

用途: backspaceAtCursor('elementid')

javascript,onclick

var text = document.getElementById(myTxtBox).value;  
text = text.substr(0,text,length-1);
document.getElementById(myTxtBox).value = text;

jquery插件在文本字段中模拟退格,在ie、ff、chrome中工作(基于 here )

jQuery.fn.extend({
backspaceAtCaret: function(){
  return this.each(function(i) {    

    if (document.selection) 
    {
        this.focus();
        sel = document.selection.createRange();
        if(sel.text.length > 0)
        {
            sel.text="";
        }
        else
        {
            sel.moveStart("character",-1);
            sel.text="";
        }
        sel.select();
    }
    else if (this.selectionStart || this.selectionStart == "0")
    { 
        var startPos = this.selectionStart;
        var endPos = this.selectionEnd;

        this.value = this.value.substring(0, startPos-1) + this.value.substring(endPos, this.value.length);
        this.selectionStart = startPos-1;
        this.selectionEnd = startPos-1;
        this.focus();
    } 
    else 
    {
        this.value=this.value.substr(0,(this.value.length-1));
        this.focus();
    }
  })
}
});