离 
	e.preventDefault();
});
document.addEventListener("dragleave",function(e){  //拖后放 
	e.preventDefault();
});
document.addEventListener("dragenter",function(e){  //拖进
	e.preventDefault();
});
document.addEventListener("dragover",function(e){  //拖来拖去  
	e.preventDefault();
});

function toast(msg)
{
	var toastDiv = document.getElementById('toast');
	if (msg) {
		toastDiv.style.display = 'block';
		toastDiv.innerHTML = msg;
	}
	else {
		toastDiv.style.display = 'none';
		toastDiv.innerHT