文本存在时显示按钮

Question

我想显示“继续”按钮，仅当用户国家/地区位于使用Javascript的该项目的国家/地区列表中并显示消息时，如果不存在则隐藏继续。 喜欢： '

美国

印度

下一部分有用户输入或选择他们的国家'

尼日利亚

美国

'所以，如果用户选择的“尼日利亚”不在我想要显示的可用国家/地区列表中他们“对不起这项服务在尼日利亚不可用” 如果他们选择像美国这样的可用国家名单。我想给他们看一个“继续按钮”任何帮助？

Answer 1

以下JS工作正常。

＆＃13;

＆＃13;

function checkAvailability(country) {
  var countryname = list.options[list.selectedIndex].text;
  if (!isInArray(country))
  {
    proceed.style.display = 'none';
    error.innerText = "*Sorry this service is not available in "+ countryname;
    console.log("Sorry this service is not available in "+ countryname);
  }
  else
  {
    proceed.style.display = 'block';
    error.innerText = "";
    console.log("Available");
  }
}
var array = ["IN","US"]; // Available countries

function isInArray(value) {
  return array.indexOf(value) > -1;
}

＆＃13;

<select id="list" onchange="checkAvailability(this.value)">
	<option value="AF">Afghanistan</option>
	<option value="AX">Åland Islands</option>
	<option value="AL">Albania</option>
	<option value="DZ">Algeria</option>
	<option value="AS">American Samoa</option>
	<option value="AD">Andorra</option>
	<option value="AO">Angola</option>
	<option value="AI">Anguilla</option>
	<option value="AQ">Antarctica</option>
	<option value="AG">Antigua and Barbuda</option>
	<option value="AR">Argentina</option>
	<option value="AM">Armenia</option>
	<option value="AW">Aruba</option>
	<option value="AU">Australia</option>
	<option value="AT">Austria</option>
	<option value="AZ">Azerbaijan</option>
	<option value="BS">Bahamas</option>
	<option value="BH">Bahrain</option>
	<option value="BD">Bangladesh</option>
	<option value="BB">Barbados</option>
	<option value="BY">Belarus</option>
	<option value="BE">Belgium</option>
	<option value="BZ">Belize</option>
	<option value="BJ">Benin</option>
	<option value="BM">Bermuda</option>
	<option value="BT">Bhutan</option>
	<option value="BO">Bolivia, Plurinational State of</option>
	<option value="BQ">Bonaire, Sint Eustatius and Saba</option>
	<option value="BA">Bosnia and Herzegovina</option>
	<option value="BW">Botswana</option>
	<option value="BV">Bouvet Island</option>
	<option value="BR">Brazil</option>
	<option value="IO">British Indian Ocean Territory</option>
	<option value="BN">Brunei Darussalam</option>
	<option value="BG">Bulgaria</option>
	<option value="BF">Burkina Faso</option>
	<option value="BI">Burundi</option>
	<option value="KH">Cambodia</option>
	<option value="CM">Cameroon</option>
	<option value="CA">Canada</option>
	<option value="CV">Cape Verde</option>
	<option value="KY">Cayman Islands</option>
	<option value="CF">Central African Republic</option>
	<option value="TD">Chad</option>
	<option value="CL">Chile</option>
	<option value="CN">China</option>
	<option value="CX">Christmas Island</option>
	<option value="CC">Cocos (Keeling) Islands</option>
	<option value="CO">Colombia</option>
	<option value="KM">Comoros</option>
	<option value="CG">Congo</option>
	<option value="CD">Congo, the Democratic Republic of the</option>
	<option value="CK">Cook Islands</option>
	<option value="CR">Costa Rica</option>
	<option value="CI">Côte d'Ivoire</option>
	<option value="HR">Croatia</option>
	<option value="CU">Cuba</option>
	<option value="CW">Curaçao</option>
	<option value="CY">Cyprus</option>
	<option value="CZ">Czech Republic</option>
	<option value="DK">Denmark</option>
	<option value="DJ">Djibouti</option>
	<option value="DM">Dominica</option>
	<option value="DO">Dominican Republic</option>
	<option value="EC">Ecuador</option>
	<option value="EG">Egypt</option>
	<option value="SV">El Salvador</option>
	<option value="GQ">Equatorial Guinea</option>
	<option value="ER">Eritrea</option>
	<option value="EE">Estonia</option>
	<option value="ET">Ethiopia</option>
	<option value="FK">Falkland Islands (Malvinas)</option>
	<option value="FO">Faroe Islands</option>
	<option value="FJ">Fiji</option>
	<option value="FI">Finland</option>
	<option value="FR">France</option>
	<option value="GF">French Guiana</option>
	<option value="PF">French Polynesia</option>
	<option value="TF">French Southern Territories</option>
	<option value="GA">Gabon</option>
	<option value="GM">Gambia</option>
	<option value="GE">Georgia</option>
	<option value="DE">Germany</option>
	<option value="GH">Ghana</option>
	<option value="GI">Gibraltar</option>
	<option value="GR">Greece</option>
	<option value="GL">Greenland</option>
	<option value="GD">Grenada</option>
	<option value="GP">Guadeloupe</option>
	<option value="GU">Guam</option>
	<option value="GT">Guatemala</option>
	<option value="GG">Guernsey</option>
	<option value="GN">Guinea</option>
	<option value="GW">Guinea-Bissau</option>
	<option value="GY">Guyana</option>
	<option value="HT">Haiti</option>
	<option value="HM">Heard Island and McDonald Islands</option>
	<option value="VA">Holy See (Vatican City State)</option>
	<option value="HN">Honduras</option>
	<option value="HK">Hong Kong</option>
	<option value="HU">Hungary</option>
	<option value="IS">Iceland</option>
	<option value="IN">India</option>
	<option value="ID">Indonesia</option>
	<option value="IR">Iran, Islamic Republic of</option>
	<option value="IQ">Iraq</option>
	<option value="IE">Ireland</option>
	<option value="IM">Isle of Man</option>
	<option value="IL">Israel</option>
	<option value="IT">Italy</option>
	<option value="JM">Jamaica</option>
	<option value="JP">Japan</option>
	<option value="JE">Jersey</option>
	<option value="JO">Jordan</option>
	<option value="KZ">Kazakhstan</option>
	<option value="KE">Kenya</option>
	<option value="KI">Kiribati</option>
	<option value="KP">Korea, Democratic People's Republic of</option>
	<option value="KR">Korea, Republic of</option>
	<option value="KW">Kuwait</option>
	<option value="KG">Kyrgyzstan</option>
	<option value="LA">Lao People's Democratic Republic</option>
	<option value="LV">Latvia</option>
	<option value="LB">Lebanon</option>
	<option value="LS">Lesotho</option>
	<option value="LR">Liberia</option>
	<option value="LY">Libya</option>
	<option value="LI">Liechtenstein</option>
	<option value="LT">Lithuania</option>
	<option value="LU">Luxembourg</option>
	<option value="MO">Macao</option>
	<option value="MK">Macedonia, the former Yugoslav Republic of</option>
	<option value="MG">Madagascar</option>
	<option value="MW">Malawi</option>
	<option value="MY">Malaysia</option>
	<option value="MV">Maldives</option>
	<option value="ML">Mali</option>
	<option value="MT">Malta</option>
	<option value="MH">Marshall Islands</option>
	<option value="MQ">Martinique</option>
	<option value="MR">Mauritania</option>
	<option value="MU">Mauritius</option>
	<option value="YT">Mayotte</option>
	<option value="MX">Mexico</option>
	<option value="FM">Micronesia, Federated States of</option>
	<option value="MD">Moldova, Republic of</option>
	<option value="MC">Monaco</option>
	<option value="MN">Mongolia</option>
	<option value="ME">Montenegro</option>
	<option value="MS">Montserrat</option>
	<option value="MA">Morocco</option>
	<option value="MZ">Mozambique</option>
	<option value="MM">Myanmar</option>
	<option value="NA">Namibia</option>
	<option value="NR">Nauru</option>
	<option value="NP">Nepal</option>
	<option value="NL">Netherlands</option>
	<option value="NC">New Caledonia</option>
	<option value="NZ">New Zealand</option>
	<option value="NI">Nicaragua</option>
	<option value="NE">Niger</option>
	<option value="NG">Nigeria</option>
	<option value="NU">Niue</option>
	<option value="NF">Norfolk Island</option>
	<option value="MP">Northern Mariana Islands</option>
	<option value="NO">Norway</option>
	<option value="OM">Oman</option>
	<option value="PK">Pakistan</option>
	<option value="PW">Palau</option>
	<option value="PS">Palestinian Territory, Occupied</option>
	<option value="PA">Panama</option>
	<option value="PG">Papua New Guinea</option>
	<option value="PY">Paraguay</option>
	<option value="PE">Peru</option>
	<option value="PH">Philippines</option>
	<option value="PN">Pitcairn</option>
	<option value="PL">Poland</option>
	<option value="PT">Portugal</option>
	<option value="PR">Puerto Rico</option>
	<option value="QA">Qatar</option>
	<option value="RE">Réunion</option>
	<option value="RO">Romania</option>
	<option value="RU">Russian Federation</option>
	<option value="RW">Rwanda</option>
	<option value="BL">Saint Barthélemy</option>
	<option value="SH">Saint Helena, Ascension and Tristan da Cunha</option>
	<option value="KN">Saint Kitts and Nevis</option>
	<option value="LC">Saint Lucia</option>
	<option value="MF">Saint Martin (French part)</option>
	<option value="PM">Saint Pierre and Miquelon</option>
	<option value="VC">Saint Vincent and the Grenadines</option>
	<option value="WS">Samoa</option>
	<option value="SM">San Marino</option>
	<option value="ST">Sao Tome and Principe</option>
	<option value="SA">Saudi Arabia</option>
	<option value="SN">Senegal</option>
	<option value="RS">Serbia</option>
	<option value="SC">Seychelles</option>
	<option value="SL">Sierra Leone</option>
	<option value="SG">Singapore</option>
	<option value="SX">Sint Maarten (Dutch part)</option>
	<option value="SK">Slovakia</option>
	<option value="SI">Slovenia</option>
	<option value="SB">Solomon Islands</option>
	<option value="SO">Somalia</option>
	<option value="ZA">South Africa</option>
	<option value="GS">South Georgia and the South Sandwich Islands</option>
	<option value="SS">South Sudan</option>
	<option value="ES">Spain</option>
	<option value="LK">Sri Lanka</option>
	<option value="SD">Sudan</option>
	<option value="SR">Suriname</option>
	<option value="SJ">Svalbard and Jan Mayen</option>
	<option value="SZ">Swaziland</option>
	<option value="SE">Sweden</option>
	<option value="CH">Switzerland</option>
	<option value="SY">Syrian Arab Republic</option>
	<option value="TW">Taiwan, Province of China</option>
	<option value="TJ">Tajikistan</option>
	<option value="TZ">Tanzania, United Republic of</option>
	<option value="TH">Thailand</option>
	<option value="TL">Timor-Leste</option>
	<option value="TG">Togo</option>
	<option value="TK">Tokelau</option>
	<option value="TO">Tonga</option>
	<option value="TT">Trinidad and Tobago</option>
	<option value="TN">Tunisia</option>
	<option value="TR">Turkey</option>
	<option value="TM">Turkmenistan</option>
	<option value="TC">Turks and Caicos Islands</option>
	<option value="TV">Tuvalu</option>
	<option value="UG">Uganda</option>
	<option value="UA">Ukraine</option>
	<option value="AE">United Arab Emirates</option>
	<option value="GB">United Kingdom</option>
	<option value="US">United States</option>
	<option value="UM">United States Minor Outlying Islands</option>
	<option value="UY">Uruguay</option>
	<option value="UZ">Uzbekistan</option>
	<option value="VU">Vanuatu</option>
	<option value="VE">Venezuela, Bolivarian Republic of</option>
	<option value="VN">Viet Nam</option>
	<option value="VG">Virgin Islands, British</option>
	<option value="VI">Virgin Islands, U.S.</option>
	<option value="WF">Wallis and Futuna</option>
	<option value="EH">Western Sahara</option>
	<option value="YE">Yemen</option>
	<option value="ZM">Zambia</option>
	<option value="ZW">Zimbabwe</option>
</select>
<input type="submit" id="proceed" value="Proceed" style="display: none">
<span id="error" style="color: red;"></span>

＆＃13;

＆＃13;

＆＃13;

Answer 2

如果您希望页面仅显示或隐藏用户在select元素中输入的国家/地区的Proceed按钮，您可以这样做：

<select id="Countries" onchange="check(this.value)">
    <option value="Select">Please select your country</option>
    <option value="AF">Afghanistan</option>
    <option value="AX">Åland Islands</option>
    <option value="AL">Albania</option>
    <option value="DZ">Algeria</option>
    <option value="AS">American Samoa</option>
    <option value="AD">Andorra</option>
    <option value="AO">Angola</option>
    <option value="AI">Anguilla</option>
    <option value="AQ">Antarctica</option>
    <option value="AG">Antigua and Barbuda</option>
    <option value="AR">Argentina</option>
    <option value="AM">Armenia</option>
    <option value="AW">Aruba</option>
    <option value="AU">Australia</option>
    <option value="AT">Austria</option>
    <option value="AZ">Azerbaijan</option>
    <option value="BS">Bahamas</option>
    <option value="BH">Bahrain</option>
    <option value="BD">Bangladesh</option>
    <option value="BB">Barbados</option>
    <option value="BY">Belarus</option>
    <option value="BE">Belgium</option>
    <option value="BZ">Belize</option>
    <option value="BJ">Benin</option>
    <option value="BM">Bermuda</option>
    <option value="BT">Bhutan</option>
    <option value="BO">Bolivia, Plurinational State of</option>
    <option value="BQ">Bonaire, Sint Eustatius and Saba</option>
    <option value="BA">Bosnia and Herzegovina</option>
    <option value="BW">Botswana</option>
    <option value="BV">Bouvet Island</option>
    <option value="BR">Brazil</option>
    <option value="IO">British Indian Ocean Territory</option>
    <option value="BN">Brunei Darussalam</option>
    <option value="BG">Bulgaria</option>
    <option value="BF">Burkina Faso</option>
    <option value="BI">Burundi</option>
    <option value="KH">Cambodia</option>
    <option value="CM">Cameroon</option>
    <option value="CA">Canada</option>
    <option value="CV">Cape Verde</option>
    <option value="KY">Cayman Islands</option>
    <option value="CF">Central African Republic</option>
    <option value="TD">Chad</option>
    <option value="CL">Chile</option>
    <option value="CN">China</option>
    <option value="CX">Christmas Island</option>
    <option value="CC">Cocos (Keeling) Islands</option>
    <option value="CO">Colombia</option>
    <option value="KM">Comoros</option>
    <option value="CG">Congo</option>
    <option value="CD">Congo, the Democratic Republic of the</option>
    <option value="CK">Cook Islands</option>
    <option value="CR">Costa Rica</option>
    <option value="CI">Côte d'Ivoire</option>
    <option value="HR">Croatia</option>
    <option value="CU">Cuba</option>
    <option value="CW">Curaçao</option>
    <option value="CY">Cyprus</option>
    <option value="CZ">Czech Republic</option>
    <option value="DK">Denmark</option>
    <option value="DJ">Djibouti</option>
    <option value="DM">Dominica</option>
    <option value="DO">Dominican Republic</option>
    <option value="EC">Ecuador</option>
    <option value="EG">Egypt</option>
    <option value="SV">El Salvador</option>
    <option value="GQ">Equatorial Guinea</option>
    <option value="ER">Eritrea</option>
    <option value="EE">Estonia</option>
    <option value="ET">Ethiopia</option>
    <option value="FK">Falkland Islands (Malvinas)</option>
    <option value="FO">Faroe Islands</option>
    <option value="FJ">Fiji</option>
    <option value="FI">Finland</option>
    <option value="FR">France</option>
    <option value="GF">French Guiana</option>
    <option value="PF">French Polynesia</option>
    <option value="TF">French Southern Territories</option>
    <option value="GA">Gabon</option>
    <option value="GM">Gambia</option>
    <option value="GE">Georgia</option>
    <option value="DE">Germany</option>
    <option value="GH">Ghana</option>
    <option value="GI">Gibraltar</option>
    <option value="GR">Greece</option>
    <option value="GL">Greenland</option>
    <option value="GD">Grenada</option>
    <option value="GP">Guadeloupe</option>
    <option value="GU">Guam</option>
    <option value="GT">Guatemala</option>
    <option value="GG">Guernsey</option>
    <option value="GN">Guinea</option>
    <option value="GW">Guinea-Bissau</option>
    <option value="GY">Guyana</option>
    <option value="HT">Haiti</option>
    <option value="HM">Heard Island and McDonald Islands</option>
    <option value="VA">Holy See (Vatican City State)</option>
    <option value="HN">Honduras</option>
    <option value="HK">Hong Kong</option>
    <option value="HU">Hungary</option>
    <option value="IS">Iceland</option>
    <option value="IN">India</option>
    <option value="ID">Indonesia</option>
    <option value="IR">Iran, Islamic Republic of</option>
    <option value="IQ">Iraq</option>
    <option value="IE">Ireland</option>
    <option value="IM">Isle of Man</option>
    <option value="IL">Israel</option>
    <option value="IT">Italy</option>
    <option value="JM">Jamaica</option>
    <option value="JP">Japan</option>
    <option value="JE">Jersey</option>
    <option value="JO">Jordan</option>
    <option value="KZ">Kazakhstan</option>
    <option value="KE">Kenya</option>
    <option value="KI">Kiribati</option>
    <option value="KP">Korea, Democratic People's Republic of</option>
    <option value="KR">Korea, Republic of</option>
    <option value="KW">Kuwait</option>
    <option value="KG">Kyrgyzstan</option>
    <option value="LA">Lao People's Democratic Republic</option>
    <option value="LV">Latvia</option>
    <option value="LB">Lebanon</option>
    <option value="LS">Lesotho</option>
    <option value="LR">Liberia</option>
    <option value="LY">Libya</option>
    <option value="LI">Liechtenstein</option>
    <option value="LT">Lithuania</option>
    <option value="LU">Luxembourg</option>
    <option value="MO">Macao</option>
    <option value="MK">Macedonia, the former Yugoslav Republic of</option>
    <option value="MG">Madagascar</option>
    <option value="MW">Malawi</option>
    <option value="MY">Malaysia</option>
    <option value="MV">Maldives</option>
    <option value="ML">Mali</option>
    <option value="MT">Malta</option>
    <option value="MH">Marshall Islands</option>
    <option value="MQ">Martinique</option>
    <option value="MR">Mauritania</option>
    <option value="MU">Mauritius</option>
    <option value="YT">Mayotte</option>
    <option value="MX">Mexico</option>
    <option value="FM">Micronesia, Federated States of</option>
    <option value="MD">Moldova, Republic of</option>
    <option value="MC">Monaco</option>
    <option value="MN">Mongolia</option>
    <option value="ME">Montenegro</option>
    <option value="MS">Montserrat</option>
    <option value="MA">Morocco</option>
    <option value="MZ">Mozambique</option>
    <option value="MM">Myanmar</option>
    <option value="NA">Namibia</option>
    <option value="NR">Nauru</option>
    <option value="NP">Nepal</option>
    <option value="NL">Netherlands</option>
    <option value="NC">New Caledonia</option>
    <option value="NZ">New Zealand</option>
    <option value="NI">Nicaragua</option>
    <option value="NE">Niger</option>
    <option value="NG">Nigeria</option>
    <option value="NU">Niue</option>
    <option value="NF">Norfolk Island</option>
    <option value="MP">Northern Mariana Islands</option>
    <option value="NO">Norway</option>
    <option value="OM">Oman</option>
    <option value="PK">Pakistan</option>
    <option value="PW">Palau</option>
    <option value="PS">Palestinian Territory, Occupied</option>
    <option value="PA">Panama</option>
    <option value="PG">Papua New Guinea</option>
    <option value="PY">Paraguay</option>
    <option value="PE">Peru</option>
    <option value="PH">Philippines</option>
    <option value="PN">Pitcairn</option>
    <option value="PL">Poland</option>
    <option value="PT">Portugal</option>
    <option value="PR">Puerto Rico</option>
    <option value="QA">Qatar</option>
    <option value="RE">Réunion</option>
    <option value="RO">Romania</option>
    <option value="RU">Russian Federation</option>
    <option value="RW">Rwanda</option>
    <option value="BL">Saint Barthélemy</option>
    <option value="SH">Saint Helena, Ascension and Tristan da Cunha</option>
    <option value="KN">Saint Kitts and Nevis</option>
    <option value="LC">Saint Lucia</option>
    <option value="MF">Saint Martin (French part)</option>
    <option value="PM">Saint Pierre and Miquelon</option>
    <option value="VC">Saint Vincent and the Grenadines</option>
    <option value="WS">Samoa</option>
    <option value="SM">San Marino</option>
    <option value="ST">Sao Tome and Principe</option>
    <option value="SA">Saudi Arabia</option>
    <option value="SN">Senegal</option>
    <option value="RS">Serbia</option>
    <option value="SC">Seychelles</option>
    <option value="SL">Sierra Leone</option>
    <option value="SG">Singapore</option>
    <option value="SX">Sint Maarten (Dutch part)</option>
    <option value="SK">Slovakia</option>
    <option value="SI">Slovenia</option>
    <option value="SB">Solomon Islands</option>
    <option value="SO">Somalia</option>
    <option value="ZA">South Africa</option>
    <option value="GS">South Georgia and the South Sandwich Islands</option>
    <option value="SS">South Sudan</option>
    <option value="ES">Spain</option>
    <option value="LK">Sri Lanka</option>
    <option value="SD">Sudan</option>
    <option value="SR">Suriname</option>
    <option value="SJ">Svalbard and Jan Mayen</option>
    <option value="SZ">Swaziland</option>
    <option value="SE">Sweden</option>
    <option value="CH">Switzerland</option>
    <option value="SY">Syrian Arab Republic</option>
    <option value="TW">Taiwan, Province of China</option>
    <option value="TJ">Tajikistan</option>
    <option value="TZ">Tanzania, United Republic of</option>
    <option value="TH">Thailand</option>
    <option value="TL">Timor-Leste</option>
    <option value="TG">Togo</option>
    <option value="TK">Tokelau</option>
    <option value="TO">Tonga</option>
    <option value="TT">Trinidad and Tobago</option>
    <option value="TN">Tunisia</option>
    <option value="TR">Turkey</option>
    <option value="TM">Turkmenistan</option>
    <option value="TC">Turks and Caicos Islands</option>
    <option value="TV">Tuvalu</option>
    <option value="UG">Uganda</option>
    <option value="UA">Ukraine</option>
    <option value="AE">United Arab Emirates</option>
    <option value="GB">United Kingdom</option>
    <option value="US">United States</option>
    <option value="UM">United States Minor Outlying Islands</option>
    <option value="UY">Uruguay</option>
    <option value="UZ">Uzbekistan</option>
    <option value="VU">Vanuatu</option>
    <option value="VE">Venezuela, Bolivarian Republic of</option>
    <option value="VN">Viet Nam</option>
    <option value="VG">Virgin Islands, British</option>
    <option value="VI">Virgin Islands, U.S.</option>
    <option value="WF">Wallis and Futuna</option>
    <option value="EH">Western Sahara</option>
    <option value="YE">Yemen</option>
    <option value="ZM">Zambia</option>
    <option value="ZW">Zimbabwe</option>
</select>
<button id="proceed">Proceed</button>

<script type="text/javascript">
function check(countrycode) {
    if(countrycode == 'Select') {document.getElementById('proceed').style.display = ''; document.getElementById('proceed').disabled = true; return;}
    else document.getElementById('proceed').disabled = false;
    if(countrycode != 'IN' && countrycode != 'US') {
        document.getElementById('proceed').style.display = 'none';
        alert('Sorry this service is not available in ' + document.getElementById('Countries').options[document.getElementById('Countries').selectedIndex].text);
    } else {
        document.getElementById('proceed').style.display = '';
    }
}

document.getElementById('Countries').value = 'Select';
document.getElementById('proceed').disabled = true;

</script>

如您所见，您还需要在select元素中选择“请选择您的国家/地区”选项，最好在页面加载时将其设置为所选选项。如果选择此选项（这意味着尚未选择任何国家/地区），则会显示“继续”按钮，但是已禁用，当选择国家/地区时，如果是印度或美国，则会显示按钮，但如果按钮是隐藏的另一个国家/地区。