分享到微信时如何自定义文字描述和图片

document.addEventListener("WeixinJSBridgeReady",
function() {
if (WeixinJSBridge) {

//分享给好友
WeixinJSBridge.on("menu:share:appmessage", function() {

WeixinJSBridge.invoke(
"sendAppMessage",
{
img_url: shareData.imgUrl,
link: shareData.timeLineLink,
desc: shareData.tContent,
title: b
}, function() {});
});
WeixinJSBridge.on("menu:share:timeline", function() {

//分享到朋友圈
WeixinJSBridge.invoke(
"shareTimeline",
{
img_url: shareData.imgUrl,
link: shareData.timeLineLink,
desc: shareData.tContent,
title: b
}, function() {});
});
}
},
false);