Optimal Way to Pass C# Variables to JS

Question

I have several functions that are written in JS that do error checking on my site. On one instance I want to disable two of the checks if a certain instance in the DB is true.

I have something like this on the aspx.cs

if (this.exemptcheck == true) {
  // could set a variable to pass or whatever is optimal here
}

Then in JS I have a function like this in my .aspx

if (NotANumberCheck(item.GetMember("TotalSpace").Value, 'Space must be Numeric') == false) { return false; }

I don't want this check to run if this.examptcheck returns true. What is the optimal way to do this? I have heard of putting variables in non-visible fields but that doesn't seem ideal. Any suggestions would be appreciated.

Thanks

Answer 1

You could write a script section in the page which sets a variable to true/false and then check for that variable in the JS later.

Answer 2

In the aspx, set a member variable called ExemptCheck. Later, in the JS, do this:

var exemptCheck = <% Response.Write(ExemptCheck.ToString()) %>;

This will give you a JS variable with the same value as the C# variable.

Answer 3

You may Response.Write() the javascript code only when this.examptcheck is true.

Answer 4

Just register your js function only if your condition is true, you don't need to check a variable:

C# code:

if (this.exemptcheck == true) {
    Page.ClientScript.RegisterStartupScript(Page.GetType(), "KEY", "/* code of your JS function that handle the true case */", true);
}

Answer 5

I ended up using the following command to set the value in the aspx.cs code

Page.ClientScript.RegisterStartupScript(this.GetType(), "", "var stackedUnknownExemptCheck = true;", true);