function imgratio() {
  //图片 ratio方法调用
  $(".ratio-img").each(function (index, element) {
    if ($(this).is(":visible")) {
      $(this).css({ height: Math.floor($(this).width() * $(this).data("ratio")) });
    }
  });
}

$(function () {
  imgratio(); //初始化图片ratio

  setTimeout(function () {
    imgratio();
  }, 100);

  $(".ratio-img").each(function (index, element) {
    $(this).attr({ src: $(this).data("src") }); //图片预加载
  });

  //窗口改变大小回调ratio；
  var rtime = new Date();
  var timeout = false;
  var delta = 200;
  $(window).resize(function () {
    rtime = new Date();
    if (timeout === false) {
      timeout = true;
      setTimeout(resizeend, delta); //resize只回调最后一次
    }
  });
  function resizeend() {
    //window.resize回调
    if (new Date() - rtime < delta) {
      setTimeout(resizeend, delta);
    } else {
      timeout = false;
      imgratio(); //ratio
    }
  }
  //
});

//无图图像
var nullimg = "../images/error.png";
function lod(t) {
  t.onerror = null;
  t.src = nullimg;
  //t.className= 'err_position';
  t.parentNode.className = "err_position";
}
$(function () {
  $(".ratio-img").each(function () {
    if ($(this).attr("src") == "") {
      $(this).attr({ src: nullimg });
    }
  });
});

$(function () {
  if (!placeholderSupport()) {
    // 判断浏览器是否支持 placeholder
    $("[placeholder]")
      .focus(function () {
        var input = $(this);
        if (input.val() == input.attr("placeholder")) {
          input.val("");
          input.removeClass("placeholder");
        }
      })
      .blur(function () {
        var input = $(this);
        if (input.val() == "" || input.val() == input.attr("placeholder")) {
          input.addClass("placeholder");
          input.val(input.attr("placeholder"));
        }
      })
      .blur();
  }
});
function placeholderSupport() {
  return "placeholder" in document.createElement("input");
}