C# .Contains() to check if it is a URL

c#, string

Solution

You could use `Uri.TryCreate` instead to see if creation of the URL is successful:

Uri targetUri;
if (Uri.TryCreate("http://" + e.CellValue, UriKind.RelativeOrAbsolute, out targetUri))
{
    //success
    attachmentUrl = "http://" + e.CellValue;
}

Problem

I don't like to post such a general question, but I am not seeing a lot on the topic, so I was wondering if anyone has done something like this, and whether or not this is a good implementation to go with. EDIT Added whole method Here is the code ``` protected void gridViewAttachments_HtmlDataCellPrepared(object sender, DevExpress.Web.ASPxGridView.ASPxGridViewTableDataCellEventArgs e) { //if (e.DataColumn.FieldName == "AttachmentName" && e.CellValue.ToString().ToLower().Contains("://")) // attachmentUrl = e.CellValue.ToString(); //if (e.DataColumn.FieldName == "AttachmentName" && !e.CellValue.ToString().ToLower().Contains("://")) // attachmentUrl = "http://" + e.CellValue; Uri targetUri; if (Uri.TryCreate("http://" + e.CellValue, UriKind.RelativeOrAbsolute, out targetUri)) { attachmentUrl = new Uri("http://" + e.CellValue); } if (e.DataColumn is DevExpress.Web.ASPxGridView.GridViewDataHyperLinkColumn) { if (attachmentUrl.ToString() == "") { DevExpress.Web.ASPxEditors.Internal.HyperLinkDisplayControl hyperlink = (e.Cell.Controls[0] as DevExpress.Web.ASPxEditors.Internal.HyperLinkDisplayControl); hyperlink.Target = "_blank"; hyperlink.NavigateUrl = ApplicationUrl + "/Attachment.ashx?key=" + hyperlink.Text; hyperlink.Text = GetWords("GENERAL.VIEW_ATTACHMENT"); } else { DevExpress.Web.ASPxEditors.Internal.HyperLinkDisplayControl hyperlink = (e.Cell.Controls[0] as DevExpress.Web.ASPxEditors.Internal.HyperLinkDisplayControl); hyperlink.Target = "_blank"; hyperlink.NavigateUrl = attachmentUrl.ToString(); hyperlink.Text = "Go to URL"; } } } ``` Pretty basic, and it works. My question is this: Is checking if the string contains :// enough to check whether or not it is a url? The reason I have to check is it is pulling the data from table and some of the fields in the table are filenames (mydoc.docx) in which case I will do something else with them. Is there another more robust check I can do in C#?

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