# ldap_connect

(PHP 4, PHP 5, PHP 7)

ldap_connect — Connect to an LDAP server

### 说明

ldap_connect ([ string `$host` = `NULL` [, int `$port` = 389 ]] ) : resource

Creates an LDAP link identifier and checks whether the given `host` and `port` are plausible.

> Note: This function does not open a connection. It checks whether the given parameters are plausible and can be used to open a connection as soon as one is needed.

### 参数

`host`

  This field supports using a hostname or, with OpenLDAP 2.x.x and later, a full LDAP URI of the form ldap://hostname:port or ldaps://hostname:port for SSL encryption.

  You can also provide multiple LDAP-URIs separated by a space as one string

  Note that hostname:port is not a supported LDAP URI as the schema is missing.

`port`

  The port to connect to. Not used when using LDAP URIs.

### 返回值

Returns a positive LDAP link identifier when the provided hostname/port combination or LDAP URI seems plausible. It's a syntactic check of the provided parameters but the server(s) will not be contacted! If the syntactic check fails it returns `FALSE`. When OpenLDAP 2.x.x is used, ldap_connect() will always return a resource as it does not actually connect but just initializes the connecting parameters. The actual connect happens with the next calls to ldap_* funcs, usually with ldap_bind().

If no arguments are specified then the link identifier of the already opened link will be returned.

### 范例

Example #1 Example of connecting to LDAP server.

    <?php

    // LDAP variables
    $ldaphost = "ldap.example.com";  // your ldap servers
    $ldapport = 389;                 // your ldap server's port number

    // Connecting to LDAP
    $ldapconn = ldap_connect($ldaphost, $ldapport)
              or die("Could not connect to $ldaphost");

    ?>

Example #2 Example of connecting securely to LDAP server.

    <?php

    // make sure your host is the correct one
    // that you issued your secure certificate to
    $ldaphost = "ldaps://ldap.example.com/";

    // Connecting to LDAP
    $ldapconn = ldap_connect($ldaphost)
              or die("Could not connect to {$ldaphost}");

    ?>

### 参见

- ldap_bind() - 绑定 LDAP 目录