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<form name="myForm">
<p>inputText1:<input type="text" name="inputText1" value="テスト"></p>
<p>inputText2:<input type="text" name="inputText2" value=""></p>
<p>inputRadio1:
<input type="radio" name="inputRadio1" id="inputRadio1-1" value="1" checked><label for="inputRadio1-1">選択1</label>
<input type="radio" name="inputRadio1" id="inputRadio1-2" value="2"><label for="inputRadio1-2">選択2</label><br>
(デフォルトで1番目の要素を選択)
</p>
<p>inputRadio2:
<input type="radio" name="inputRadio2" id="inputRadio2-1" value="1"><label for="inputRadio2-1">選択1</label>
<input type="radio" name="inputRadio2" id="inputRadio2-2" value="2"><label for="inputRadio2-2">選択2</label>
</p>
<p>inputCheck:
<input type="checkbox" name="inputCheck" id="inputCheck1" value="1"><label for="inputCheck1">選択1</label>
<input type="checkbox" name="inputCheck" id="inputCheck2" value="2"><label for="inputCheck2">選択2</label></p>
<p>selectBox1:
<select size="1" name="selectBox1">
<option>選択1</option>
<option selected>選択2</option>
<option>選択3</option>
</select><br>(デフォルトで2番目の要素を選択)</p>
<p>selectBox2:
<select size="1" name="selectBox2">
<option>選択1</option>
<option>選択2</option>
<option>選択3</option>
</select></p>
<p>テキストエリア:<textarea rows="4" cols="40" name="textareaBox">テキスト</textarea></p>
<p>ボタン:<button type="button" name="btn">ボタン</button></p>
<p>リセットボタン:<button type="reset" name="btnReset">リセット</button></p>
<p>送信ボタン:<button type="submit" name="btnSubmit">送信</button></p>
</form>
/*------------------------------------
テキストボックス
passwordやemailなど、テキストボックス系はすべて同じです。
------------------------------------*/
// inputText1の値を取得
var vt1 = document.forms["myForm"]["inputText1"].value;
console.log( "inputText1の値:" + vt1 );
// inputText2を入力不可にする(trueで使用不可)
document.forms["myForm"]["inputText2"].disabled = true;
/*------------------------------------
ラジオボタンとチェックボックス
------------------------------------*/
// inputRadio1の1番目の要素が選択されているかの論理値を取得
var vr1 = document.forms["myForm"]["inputRadio1"][0].checked;
console.log( "inputRadio1の1番目の要素が選択されているか:" + vr1 );
// inputRadio1の要素数を取得
var vr2 = document.forms["myForm"]["inputRadio1"].length;
console.log( "inputRadio1の要素数:" + vr2 );
// inputRadio1の1番目の要素がデフォルトで選択されているか
var vr3 = document.forms["myForm"]["inputRadio1"][0].defaultChecked;
console.log( "inputRadio1の1番目の要素がデフォルトか:" + vr3);
// inputRadio2の2番目の要素を選択する
document.forms["myForm"]["inputRadio2"][1].checked = true;
// inputCheckの1番目の要素を選択する
document.forms["myForm"]["inputCheck"][0].checked=true;
// inputCheckの2番目の要素を選択不可にする
document.forms["myForm"]["inputCheck"][1].disabled = true;
/*------------------------------------
セレクトボックス
------------------------------------*/
// selectBox1の選択された項目のインデックスを返す
var vs1 = document.forms["myForm"]["selectBox1"].selectedIndex
console.log( "selectBox1の選択された項目のインデックス:" + vs1 );
// selectBox1の選択された要素のテキストを取得
var vs2 = document.forms["myForm"]["selectBox1"][vs1].text;
console.log( "selectBox1の選択された要素のテキスト:" + vs2 );
// selectBox2の最後の要素を選択
document.forms["myForm"]["selectBox2"][document.forms["myForm"]["selectBox2"].length-1].selected = true;
// selectBox2の項目毎の処理
for ( var i=0; i<document.forms["myForm"]["selectBox2"].length; i++ ){
// 項目が選択されているかの論理値を取得
var vs3 = document.forms["myForm"]["selectBox2"][i].text;
console.log( i + "番目の項目のテキスト:" + vs3 );
}
/*------------------------------------
テキストエリア
------------------------------------*/
// textareaBoxのフォーカスイベントをキャッチ
document.forms["myForm"]["textareaBox"].addEventListener( "focus", function(){
// テキストエリアの文字を選択
document.forms["myForm"]["textareaBox"].select()
;
// テキストエリアの高さを変更
document.forms["myForm"]["textareaBox"].rows=10
;
} );
/*------------------------------------
ボタン
------------------------------------*/
// ボタンのクリックイベントをリスナーに登録
document.forms["myForm"]["btn"].addEventListener( "click", function(){
alert( "ボタンがクリックされました" );
} );
// btnResetボタンをクリック不可
document.forms["myForm"]["btnReset"].disabled = true;
// ボタンのクリックイベントをリスナーに登録
document.forms["myForm"].addEventListener( "submit", function( evt ){
alert( "送信をキャンセルします" );
evt.preventDefault();
} );
/*
// 項目のインデックス番号を返す
console.log(document.forms["myForm"]["selectBox2"][0].index+ " "+document.forms["myForm"]["selectBox2"][1].index);
// TYPE属性を変更
//document.forms["myForm"]["inputText"].type="radio";
document.forms["myForm"]["button"].disabled=true;
*/
Also see: Tab Triggers