formPost (url, params) {
      var form = document.createElement('form')
      form.action = url
      form.target = 'myIframe'
      form.method = 'post'
      // form.style.dispaly = "none";

      //添加参数
      for (var i in params) {
        var opt = document.createElement('input')
        opt.name = params[i].name
        opt.value = params[i].value
        form.appendChild(opt)
      }
      document.body.appendChild(form)
      form.submit()
      document.body.removeChild(form)
    }