Javascript 通用异步回调函数
召集人:Javascript 通用异步回调函数,javascript,Javascript,召集人: this.init = function (onupgradeneeded, onsuccess) { var openRequest = indexedDB.open(dbName); openRequest.onupgradeneeded = function (e) { db = e.target.result; if (!db.objectStoreNames.contains(ob
this.init = function (onupgradeneeded, onsuccess) {
var openRequest = indexedDB.open(dbName);
openRequest.onupgradeneeded = function (e) {
db = e.target.result;
if (!db.objectStoreNames.contains(objectStoreName)) {
console.log('Creating the ' + objectStoreName + ' objectstore');
db.createObjectStore(objectStoreName, { keyPath: "id", autoIncrement: true });
}
};
openRequest.onsuccess = function (e) {
db = e.target.result;
db.onerror = function (event) {
// Generic error handler for all errors targeted at this database requests
console.log("Database error: " + event.target.errorCode);
};
};
};
当init函数运行时,它将在openRequest.onupgradeneeded
或openRequest.onsuccess
中结束
我想知道的是,是否有可能创建一个在两个函数中都被调用的通用回调函数。因此,无论运行两个函数中的哪一个,我都可以通过使用
var idb = new Demo.IndexedDB();
idb.init();
希望你明白,否则我会详细说明
谢谢只需传入一个回调函数,并在两种情况下调用该回调函数:
idb.init(function(){
//onupgradeneeded or onsuccess completed
});
只需传入一个回调函数,并在两种情况下调用该回调函数:
idb.init(function(){
//onupgradeneeded or onsuccess completed
});
只需使
.init
接受一个参数,并在两个回调中调用传递的参数即可。@FelixKling刚刚注意到。有时这比你想象的要容易:-)谢谢必须让.init
接受一个参数,并在两个回调中调用传递的参数。@FelixKling刚刚注意到。有时比你想象的要容易:-)谢谢谢谢。有时候比你想象的要容易:-)谢谢。有时候,这比你想象的要容易:-)