Insert/Save CustomObject and account fields using visualforce page?

Question

For external users, we will be sending a link in the email to fill survey and when they click submit.

1. A record should be created/saved into salesforce custom Object(Survey__c)

2. This Survey object has a lookup field which is Account, this should also be saved.

How do I achieve this?

Below is my code:

VisualForce Page

<apex:page controller="myAudit">
    <apex:form >
        <apex:pageblock >
            <apex:inputField  value="{!account.name}"/>
            <apex:inputText id="Survey" value="{!txtSurvey}"/>
              <apex:commandButton action="{!save}" value="save"/>
        </apex:pageblock>
    </apex:form>
</apex:page>

Controller

public class myAudit {

    public String account { get; set; }
    public String txtAuditQ { get; set; }
    public PageReference save() {
        //Add your custom logic to update specific fields here 
        Survey__c aq = new Survey__c();
        aq.Name = txtSurvey;
        aq.account__c = account;
        insert aq;
        return null;
    }
  }
}

Answer 1

According to your code aq.account__c = account; You are assigning Account which is string to the lookup field. Thats why it is not giving you AccountId after saving.

Small changes are suggested.

Declare Account as object instead of String

public Account accountObj { get; set; }

In the visualforce, for <apex:inputField> use Account.Id, which will give you Account Lookup.

<apex:inputField  value="{!accountObj.Id}"/>

In the Controller make this change aq.account__c = accountObj.Id;

Controller

public class myAudit {

    public Account accountObj { get; set; }
    public String txtAuditQ { get; set; }

    public PageReference save() {
        //Add your custom logic to update specific fields here 
        Survey__c aq = new Survey__c();
        aq.Name = txtSurvey;
        aq.account__c = accountObj.Id;
        insert aq;
        return null;
    }
  }
}

Finally, since you are performing DML so use try-catch block as a matter of best practices.