Promise在await报错后，如何继续往下跑...

 1、resolve

当a>0时，正常状况依次输出A、B、C

console.log("A");
	let result = await this.test();
	console.log("C:",result);

	private  test(){
		return new Promise((resolve,reject)=>{
			console.log("B");
			let a = 3;
			if(a > 0){
				resolve(a);
			}else{
				reject(0);
			}
		});
	}

 

2、没有处理失败信息，致使程序没法继续执行

当a<0时。输出A、B后，C没法输出，程序没法继续往下执行。

console.log("A");
	let result = await this.test();
	console.log("C:",result);

	private  test(){
		return new Promise((resolve,reject)=>{
			console.log("B");
			let a = -3;
			if(a > 0){
				resolve(a);
			}else{
				reject(0);
			}
		});
	}

 

3、catch

增长catch处理错误，程序能够继续执行

console.log("A");
	let result = await this.test();
	console.log("C:",result);

	private  test(){
		return new Promise((resolve,reject)=>{
			console.log("B");
			let a = -3;
			if(a > 0){
				resolve(a);
			}else{
				reject(0);
			}
		}).catch((err)=>{ console.log("err:", err); });
	}

 

这样也能够

let result = await this.test().catch(()=>{});

　　

 

4、使用then处理错误，程序继续执行

 换一种写法，使用then。

console.log("A");
	let result = await this.test().then((res)=>{
		console.log("success:", res);
	},(res)=>{
		console.log("fail:", res);
	});
	console.log("C:",result);


	private  test(){
		return new Promise((resolve,reject)=>{
			console.log("B");
			let a = -3;
			if(a > 0){
				resolve(a);
			}else{
				reject(0);
			}
		});
	}

 

 

5、在await处使用catch，程序继续执行

protected async createGameScene() {
        console.log("A");
        let result = await this.test().catch((err)=>{console.log("err:",err)});
        console.log("C:",result);
    }

    private  test(){
        return new Promise((resolve,reject)=>{
            console.log("B");
            let a = -3;
            if(a > 0){
                resolve(a);
            }else{
                reject(0);
            }
        });
    }

 

 

 

6、在test里catch后，程序会不执行then的reject，而是resolve。

protected async createGameScene() {
        console.log("A");
       let result = await this.test().then((res)=>{
           console.log("C:",res);
       },(res)=>{
           console.log("D:",res)
       }).catch((err)=>{console.log("E:",err)});
    console.log("F:",result);
    }

    private  test(){
        return new Promise((resolve,reject)=>{
            console.log("B");
            let a = -3;
            if(a > 0){
                resolve(a);
            }else{
                reject(0);
            }
        }).catch((err)=>{console.log("test err:", err)});
    }