Question

我想将数据推送到Firebase数据库时生成密钥。我想用自己的功能来处理它们，

所以问题在于，当用户填写表单时，他会将数据发送到我们的实时数据库，其中包含一些图像（可选），而我不需要让该图像对象在DB中为空，因此如何处理该图像，以及当用户需要发送图像时，我想将此图像以相同顺序保存，而不是以“新顺序”保存。

节点

这是我的功能

handleOrder = () => {
    const { nameOfProblem, description, userId, imageOfPrblem, providerId } = this.state;
    const PushData = firebase.database().ref("request/" + providerId + "/" + userId + "/orders/");
    const ref = firebase.storage().ref("users/" + userId + "/UserImageOrders/" + path);
    let file = imageOfPrblem.uri;
    const path = "img_" + imageOfPrblem.fileName;
    var newOrderRef = PushData.push({
        nameOfProblem: nameOfProblem,
        description: description,
    });
    if (file) {
        let keyG = newOrderRef.key; // Key Generated with .push()
        PushData.child(keyG).update({ // didn't updated the key generated just add new element with new key !!
            imageOfPrblem: imageOfPrblem
        });
        ref.put(file).then(() => {
            console.log("File uploaded..")
        });
    }
}

handleImages = () => {
    const options = {
        title: "Select Images!",
        storageOptions: {
            skipBackup: true,
            path: "images"
        }
    };
    ImagePicker.showImagePicker(options, response => {
        console.log("Response = ", response);
        if (response.uri) {
            this.setState({ imageOfPrblem: response });
        }
        if (response.didCancel) {
            console.log("User cancelled image picker");
        } else if (response.error) {
            console.log("ImagePicker Error: ", response.error);
        } else if (response.customButton) {
            console.log("User tapped custom button: ", response.customButton);
            alert(response.customButton);
        }
    });
};

Answer 1

来自任何Firebase快照ref的推送ID位于ref.name()中。

Answer 2

这对我来说似乎很好：

var ref = firebase.database().ref("/55912103");

var newChildRef = ref.push({ firstChild: true });
console.log("new key: "+newChildRef.key);
ref.child(newChildRef.key).update({ secondChild: true });

运行此代码后，我将在新孩子的密钥中记录该JSON：

"-LdgLWu_wBNNicFlPDGj" : {
  "firstChild" : true,
  "secondChild" : true
}

实时演示：https://jsbin.com/hovoleh/edit?js,console

实时JSON：https://stackoverflow.firebaseio.com/55912103.json?print=pretty

更新：如果只想将现有数据和新数据都写入 new 位置：

var newOrderRef = PushData.push({
    nameOfProblem: nameOfProblem,
    description: description,
});
if (file) {
    let keyG = newOrderRef.key; // Key Generated with .push()
    PushData.child(keyG).update({
        nameOfProblem: nameOfProblem,
        description: description,
        imageOfPrblem: imageOfPrblem
    });
    ref.put(file).then(() => {
        console.log("File uploaded..")
    });
}

Answer 3

我知道作者创建帖子已经有一段时间了，但也许有人会发现它很有用。

上面的答案有点错误，因为例如在：newChildRef

var ref = firebase.database().ref("/55912103");

var newChildRef = ref.push({ firstChild: true });

newChildRef <--- promise

ref = rdb.ref('name_of_your_ref');
    var childRef = ref.push({
        IdUser: currentUserId,
        ProductCategory: pCategory,
        ProductDescription: pDesc,
        ProductId: pId,
        ProductName: pName,
        ProductPrice: pPrice,
        ProductQuantity: pQuan
    }).catch(err => console.log(err.message));
    childRef.then(item => {
        ref.child(item.key).update({
            IdKey: item.key
        }).then(() => history.push('/delivery/basket'));
    });

你好，马修

如何在Firebase中获取按键？

3 个答案: