pass server side errors to client side typescript using vs code

siva nathan

Hi All,

am having a class with businesslogic validate the input paramerters if true save the data else return the error msg to client side typescript and show an alert

ex:

name already exists in DB need to show particular error msg to angular alert Data already exists using vs code async and await

2 Replies

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P K5y ago
You can simply returns the error message with status code from backend API response to frontend API Like
public class Response
{
public object Data { get; set; }
public string Message { get; set; }
public int Status { get; set; }
public ResponseWrapper() { }
public Response(object data, string message, int status)
{
Status = status;
Message = message;
Data = data;
}
}
In response you can return message with status code from your API like

if record exists then returns response as below or whatever your check return msg according to that

returns new Response(data,'Already exists',StatusCodes.Status500InternalServerError);

you need to handle it based on API response at front end in angular where your calling API method like
save(payload) {
service.saveAPI(payload).subscribe(response => {
if (response.body.status == 200) {
this.data= response.body.data;
}
else {
alert(response.body.message);
}
}, error => {
alert(error.message);
});
}
0
Kiran Mohanty5y ago
Hi,
You can throw exception from server side based on your condition and then in Angular , add alert in error callback method as below.
if(condition){
   //no error logic
}
else{
    throw new Exception("Name already exist in DB");
}
Angular code
this.service.apiAction()
    .subscribe(
      result => {
        // Handle no error result
      },
      error => {
        alert(error);
      }
    );
0