Pass a value to javascript from code behind

Question

I need to pass a value to javascript from code behind.

ScriptManager.RegisterStartupScript(this.Page, this.GetType(), "script", "<script type='text/javascript'>OpenPopUp();</script>", false);

JS:

function OpenPopUp(parameterValue) {           
        paramframe = parameterValue;            
        openmodal(paramframe);
    }

So parameterValue will have ID.Text value which is passed from code behind.

I need to pass a value from code behind in this function OpenPopUp to javascript.

I tried below code and the javascript doesn't fire. Am I passing the value correct to JS.

ScriptManager.RegisterStartupScript(this.Page, this.GetType(), "script", "<script type='text/javascript'>OpenPopUp(" + ID.Text + ");</script>", false);

ID.Text is a ItemTemplate value of a LinkButton in a gridview.

@erikscandola - I'm not getting any error. The JS function doesn't fire when I send the value. — Learner, Dec 17 '18 at 11:16
Possible duplicate of [Passing variable from ASP.net to JavaScript](https://stackoverflow.com/questions/10540217/passing-variable-from-asp-net-to-javascript) — Liam, Dec 17 '18 at 11:18
Your making this a lot more [complicated than you need to](https://stackoverflow.com/a/10540274/542251) — Liam, Dec 17 '18 at 11:19
@Learner I saw only a problem. If `OpenPopUp(" + ID.text + ");` will contains a text like `Hello Word`. So `OpenPopUp(Hello Word)` thrown an error. Try in this way: `OpenPopUp('" + ID.text + "');` — erikscandola, Dec 17 '18 at 11:20
@Learner answered your question, just try that and let me know if it worked — , Dec 17 '18 at 11:26

score 2 · Accepted Answer · answered Dec 17 '18 at 11:18

2

try this, this should work

ScriptManager.RegisterStartupScript(this, typeof(string), "script1", "SampleJSFunction('" + vls_variable.Text+ "');", true);

answered Dec 17 '18 at 11:18

score 0 · Answer 2 · answered Dec 17 '18 at 11:37

generally I would use a hidden parameter and access it from javascript and C# like this

ASP.NET

<asp:HiddenField runat="server" ID="HiddenFieldID" />

javascript

var FieldName= document.getElementById('<%=HiddenFieldID.ClientID%>').value;

and C#

var x = HiddenFieldID.Value

note that hidden fields have string as their value,. I prefer this way so that code is easier to maintain in the future.

Pass a value to javascript from code behind

2 Answers2