请尝试从客户端创建Vehicle，但始终收到此错误将Value null转换为类型'system.int32''Id'时出错。用邮递员创建一辆车很完美。
这些是我的vehicle.component.ts代码
from tkinter import *
def draw_curve():
from math import cos, exp
w, h, colors = width//2, height//2, ('#0F0','#F00','#00F')
for n in range(3): # loop over curves
xa, ya, xb, yb = 0, h, 0, h # initial position for each curve
for x in range(w+1): # loop over horizontal axis
t = 2*x/w - 1 # parameter t moves over range [-1,1]
if n == 2: # draw damped cosine wave
xa, ya, xb, yb = xb, yb, 2*x, h + h*exp(-5*t*t)*cos(25*t)
elif n == 1: # draw negative bell curve
xa, ya, xb, yb = xb, yb, 2*x, h + h*exp(-5*t*t)
elif n == 0: # draw positive bell curve
xa, ya, xb, yb = xb, yb, 2*x, h - h*exp(-5*t*t)
canvas.create_line(xa, ya, xb, yb, width=1, fill=colors[n])
def draw_grid():
steps = 20 # number of grid steps
dw, dh = width/steps, height/steps # horizontal and vertical steps
for n in range(steps):
canvas.create_line(0, n*dh, width, n*dh, width=1, dash=(1,1))
canvas.create_line(n*dw, 0, n*dw, height, width=1, dash=(1,1))
canvas.create_rectangle(2, 2, width-1, height-1, width=1)
width, height = 800, 600
win = Tk()
canvas = Canvas(win, width=width, height=height)
canvas.pack(padx=5, pady=5)
draw_grid()
draw_curve()
win.mainloop()
和Vehicle.ts
makes:any=[];
models:any[];
features: any=[];
vehicle: SaveVehicle={
id:0,
makeId:0,
modelId:0,
features:[],
isRegistered:false,
contact: {
name:'',
phone:'',
email:''
}
};
constructor(private route:ActivatedRoute,private router:Router,
private makeService:MakeService,private toastr:ToastrService) {
route.params.subscribe(p=>{
this.vehicle.id= +p['id'];
});
}
ngOnInit() {
var sources = [
this.makeService.getMakes(),
this.makeService.getFeatures()
];
if(this.vehicle.id){
sources.push(this.makeService.getVehicle(this.vehicle.id));
}
forkJoin(sources).subscribe(data=>{
this.makes = data[0];
this.features=data[1];
if(this.vehicle.id){
this.setVehicle(<any>data[2]);
this.populateModels();
}
},
err=>{
if(err.status==404){
this.router.navigate(['/home']);
}
})
}
private populateModels(){
var selectedMake = this.makes.find(m=>m.id==this.vehicle.makeId);
this.models = selectedMake? selectedMake.models:[];
}
private setVehicle(v:Vehicle){
+this.vehicle.id;
this.vehicle.id=v.id;
this.vehicle.modelId=v.model.id;
this.vehicle.makeId=v.make.id;
this.vehicle.isRegistered=v.isRegistered;
this.vehicle.contact=v.contact;
this.vehicle.features=_.pluck(v.features,'id');
}
submit(){
if(this.vehicle.id){
this.makeService.updateVehicle(this.vehicle).subscribe(
x=>{
this.toastr.success('Vehicle Updated successfully','Success');
},
err=>{
console.log(err);
}
);
}else{
console.log(this.vehicle);
this.makeService.createVehicle(this.vehicle).subscribe(
x=>{console.log(x)
this.toastr.success('Success', 'Vehicle created successfully');},
err=>{
console.log(err);
}
);
}
请尽快帮助我解决此问题。目前正在获取空车辆ID。 预先感谢