jQuery: brought val into line with documentation

Plus added val test suite

jquery/jquery-tests.ts

@@ -2309,6 +2309,56 @@ function test_prop() {
     var title: string = $('option:selected', this).prop('title');
 }
 
+function test_val() {
+    // Get the value from a dropdown select
+    $("select.foo option:selected").val();
+
+    // Get the value from a dropdown select even easier
+    $("select.foo").val();
+
+    // Get the value from a checked checkbox
+    $("input:checkbox:checked").val();
+
+    // Get the value from a set of radio buttons
+    $("input:radio[name=bar]:checked").val();
+
+    function displayVals() {
+        var singleValues = $("#single").val();
+        var multipleValues = $("#multiple").val() || [];
+        $("p").html("<b>Single:</b> " + singleValues +
+            " <b>Multiple:</b> " + multipleValues.join(", "));
+    }
+
+    $("select").change(displayVals);
+    displayVals();
+
+
+    $("input")
+        .keyup(function () {
+            var value = $(this).val();
+            $("p").text(value);
+        })
+        .keyup();
+
+    $("input:text.items").val(function (index, value) {
+        return value + " " + this.className;
+    });
+
+    $("button").click(function () {
+        var text = $(this).text();
+        $("input").val(text);
+    });
+
+    $("input").on("blur", function () {
+        $(this).val(function (i, val) {
+            return val.toUpperCase();
+        });
+    });
+
+    $("#single").val("Single2");
+    $("#multiple").val(["Multiple2", "Multiple3"]);
+    $("input").val(["check1", "check2", "radio1"]);
+}
 
 function test_selector() {
   var $main = $('#main');

jquery/jquery.d.ts

@@ -877,11 +877,28 @@ interface JQuery {
      */
     toggleClass(func: (index: number, className: string, swtch: boolean) => string, swtch?: boolean): JQuery;
 
+    /**
+     * Get the current value of the first element in the set of matched elements.
+     */
     val(): any;
-    val(value: string[]): JQuery;
+    /**
+     * Set the value of each element in the set of matched elements.
+     *
+     * @param value A string of text or an array of strings corresponding to the value of each matched element to set as selected/checked.
+     */
     val(value: string): JQuery;
-    val(value: number): JQuery;
-    val(func: (index: any, value: any) => any): JQuery;
+    /**
+     * Set the value of each element in the set of matched elements.
+     *
+     * @param value A string of text or an array of strings corresponding to the value of each matched element to set as selected/checked.
+     */
+    val(value: string[]): JQuery;
+    /**
+     * Set the value of each element in the set of matched elements.
+     *
+     * @param func A function returning the value to set. this is the current element. Receives the index position of the element in the set and the old value as arguments.
+     */
+    val(func: (index: number, value: any) => any): JQuery;
 
     /**
      * Get the value of style properties for the first element in the set of matched elements.