Code Sample: Custom Keyword Search Web Part Code

using System;
using System.ComponentModel;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using Microsoft.SharePoint;
using Microsoft.SharePoint.WebControls;
using Microsoft.Office.Server.Search.Query;
using Microsoft.Office.Server.Search.Administration;
using System.Data;

namespace CustomKeywordSearch.Custom_Keyword_Search
{
    [ToolboxItemAttribute(false)]
    public class Custom_Keyword_Search : WebPart
    {
        Button queryButton;
        TextBox queryTextBox;
        Label resultsLabel;
        DataGrid resultsGrid;

        
        protected override void CreateChildControls()
        {
            Controls.Clear();
            queryTextBox = new TextBox();
            this.Controls.Add(queryTextBox);
            queryButton = new Button();
            queryButton.Text = "Start Search";
            queryButton.Click += new EventHandler(queryButton_Click);
            this.Controls.Add(queryButton);
            resultsLabel = new Label();
            this.Controls.Add(resultsLabel);
        }

        void ExecuteKeywordQuery(string queryText)
        {
            SearchServiceApplicationProxy proxy = (SearchServiceApplicationProxy)SearchServiceApplicationProxy.GetProxy
(SPServiceContext.GetContext(SPContext.Current.Site));
            KeywordQuery query = new KeywordQuery(proxy);
            query.ResultsProvider = Microsoft.Office.Server.Search.Query.SearchProvider.Default;
            query.QueryText = queryText;
            query.ResultTypes |= ResultType.RelevantResults;
            ResultTableCollection searchResults = query.Execute();
            if (searchResults.Exists(ResultType.RelevantResults))
            {
                ResultTable searchResult = searchResults[ResultType.RelevantResults];
                DataTable result = new DataTable();
                result.TableName = "Result";
                result.Load(searchResult, LoadOption.OverwriteChanges);
                FillResultsGrid(result);
            }

        }

        private void FillResultsGrid(DataTable resultTable)
        {
            //Instantiate the DataGrid
            resultsGrid = new DataGrid();
            //Set the DataSource
            resultsGrid.DataSource = resultTable;
            //Bind the data to the DataGrid
            resultsGrid.DataBind();
            //Add the DataGrid to the controls
            Controls.Add(resultsGrid);
        }

        void queryButton_Click(object sender, EventArgs e)
        {
            if (queryTextBox.Text != string.Empty)
            {
                ExecuteKeywordQuery(queryTextBox.Text);
            }
            else
            {
                resultsLabel.Text = "You must enter a search word.";
            }
        }
    }
}