change( limit){
var size = "";
if( limit < 0.1 * 1024){ //小于0.1KB，则转化成B
size = limit. toFixed( 2) + "B"
} else if( limit < 0.1 * 1024 * 1024){ //小于0.1MB，则转化成KB
size = ( limit/ 1024). toFixed( 2) + "KB"
} else if( limit < 0.1 * 1024 * 1024 * 1024){ //小于0.1GB，则转化成MB
size = ( limit/( 1024 * 1024)). toFixed( 2) + "MB"
} else{ //其他转化成GB
size = ( limit/( 1024 * 1024 * 1024)). toFixed( 2) + "GB"
}
var sizeStr = size + ""; //转成字符串
var index = sizeStr. indexOf( "."); //获取小数点处的索引
var dou = sizeStr. substr( index + 1 , 2) //获取小数点后两位的值
if( dou == "00"){ //判断后两位是否为00，如果是则删除00
return sizeStr. substring( 0, index) + sizeStr. substr( index + 3, 2)
}
return size;
}