Using Session Memory with CRM Portals

Recently while doing some client work, we noticed that CRM Portals does a post back when adding information within a sub-grid on an entity form.  Why is this an issue?  Because, if you have input fields on the form, these values are not written into  CRM till the save button at the bottom of the form is clicked.  So if a user inputs anything into the sub-grid after they fill in the fields, the post back action will remove what the user input.  This can make for a bad user experience.  To over come this, we can use session memory to temporarily store the values till the browsing session is ended.

To use session storage the first thing we will need to do is register onChange handlers to update the values the session memory when the user changes a value.  Here are some examples of onChange handlers written in JQuery:

1:  $(document).on('change', '#CHECKBOX ID', function () { SetSessionValue("#CHECKBOX ID") });  
2:  $(document).on('change keyup paste', '#TEXTBOX ID', function () { SetSessionValue("#TEXTBOX ID) });  

#1 is for check boxes and picklists
#2 is for textbox inputs

The SetSessionValue is a reusable function I created to handle boolean, string and picklist.  Check my blog post on DateTime fields on how to handle onChange events with them.  Before we get into the source code for the SetSessionValue function, CRM Portals adds an _0 and _1 to the ID for boolean input on the portal.  That is why you see me add an _1 in the source code below:

1:  function SetSessionValue(fieldname) {  
2:    if ($(fieldname).hasClass('boolean-radio')) {  
3:      if ($(fieldname + "_1").is(':checked')) {  
4:        sessionStorage.setItem(fieldname, true);  
5:      }  
6:      else {  
7:        sessionStorage.setItem(fieldname, false);  
8:      }  
9:    }  
10:    else {  
11:      var fieldValue = null;  
12:      if ($(fieldname).hasClass('picklist')) {  
13:        fieldValue = $(fieldname).find(":selected").val();  
14:      }  
15:      else {  
16:        fieldValue = $(fieldname).val();  
17:      }  
18:      sessionStorage.setItem(fieldname, fieldValue);  
19:    }  
20:  }  

To get the value out of session memory I created a small reusable function for that as well:

1:  function GetSessionValue(fieldname) {  
2:    var sessionValue = sessionStorage.getItem(fieldname);  
3:    return sessionValue;  
4:  }  

Now with these parts we are writing and reading from session memory.  All  you need to do know is add a window.onload = function(){} or a $(document).ready to your code to populate your fields when a post back occurs.