这里显示系统所支持的所有函数,和自定义函数
Array
(
    [internal] => Array
        (
            [0] => zend_version
            [1] => func_num_args
            [2] => func_get_arg
            [3] => func_get_args
            [4] => strlen
            [5] => strcmp
            [6] => strncmp
            [7] => strcasecmp
            [8] => strncasecmp
            [9] => each
            [10] => error_reporting
            [11] => define
            [12] => defined
            [13] => get_class
            [14] => get_parent_class
            [15] => method_exists
            [16] => property_exists
            [17] => class_exists
            [18] => interface_exists
            [19] => function_exists
            [20] => get_included_files
            [21] => get_required_files
            [22] => is_subclass_of
            [23] => is_a
            [24] => get_class_vars
            [25] => get_object_vars
            [26] => get_class_methods
            [27] => trigger_error
            [28] => user_error
            [29] => set_error_handler
            [30] => restore_error_handler
            [31] => set_exception_handler
            [32] => restore_exception_handler
            [33] => get_declared_classes
            [34] => get_declared_interfaces
            [35] => get_defined_functions
            [36] => get_defined_vars
            [37] => create_function
            [38] => get_resource_type
            [39] => get_loaded_extensions
            [40] => extension_loaded
            [41] => get_extension_funcs
            [42] => get_defined_constants
            [43] => debug_backtrace
            [44] => debug_print_backtrace
            [45] => bcadd
            [46] => bcsub
            [47] => bcmul
            [48] => bcdiv
            [49] => bcmod
            [50] => bcpow
            [51] => bcsqrt
            [52] => bcscale
            [53] => bccomp
            [54] => bcpowmod
            [55] => jdtogregorian
            [56] => gregoriantojd
            [57] => jdtojulian
            [58] => juliantojd
            [59] => jdtojewish
            [60] => jewishtojd
            [61] => jdtofrench
            [62] => frenchtojd
            [63] => jddayofweek
            [64] => jdmonthname
            [65] => easter_date
            [66] => easter_days
            [67] => unixtojd
            [68] => jdtounix
            [69] => cal_to_jd
            [70] => cal_from_jd
            [71] => cal_days_in_month
            [72] => cal_info
            [73] => variant_set
            [74] => variant_add
            [75] => variant_cat
            [76] => variant_sub
            [77] => variant_mul
            [78] => variant_and
            [79] => variant_div
            [80] => variant_eqv
            [81] => variant_idiv
            [82] => variant_imp
            [83] => variant_mod
            [84] => variant_or
            [85] => variant_pow
            [86] => variant_xor
            [87] => variant_abs
            [88] => variant_fix
            [89] => variant_int
            [90] => variant_neg
            [91] => variant_not
            [92] => variant_round
            [93] => variant_cmp
            [94] => variant_date_to_timestamp
            [95] => variant_date_from_timestamp
            [96] => variant_get_type
            [97] => variant_set_type
            [98] => variant_cast
            [99] => com_create_guid
            [100] => com_event_sink
            [101] => com_print_typeinfo
            [102] => com_message_pump
            [103] => com_load_typelib
            [104] => com_get_active_object
            [105] => ctype_alnum
            [106] => ctype_alpha
            [107] => ctype_cntrl
            [108] => ctype_digit
            [109] => ctype_lower
            [110] => ctype_graph
            [111] => ctype_print
            [112] => ctype_punct
            [113] => ctype_space
            [114] => ctype_upper
            [115] => ctype_xdigit
            [116] => strtotime
            [117] => date
            [118] => idate
            [119] => gmdate
            [120] => mktime
            [121] => gmmktime
            [122] => checkdate
            [123] => strftime
            [124] => gmstrftime
            [125] => time
            [126] => localtime
            [127] => getdate
            [128] => date_create
            [129] => date_parse
            [130] => date_format
            [131] => date_modify
            [132] => date_timezone_get
            [133] => date_timezone_set
            [134] => date_offset_get
            [135] => date_time_set
            [136] => date_date_set
            [137] => date_isodate_set
            [138] => timezone_open
            [139] => timezone_name_get
            [140] => timezone_name_from_abbr
            [141] => timezone_offset_get
            [142] => timezone_transitions_get
            [143] => timezone_identifiers_list
            [144] => timezone_abbreviations_list
            [145] => date_default_timezone_set
            [146] => date_default_timezone_get
            [147] => date_sunrise
            [148] => date_sunset
            [149] => date_sun_info
            [150] => filter_input
            [151] => filter_var
            [152] => filter_input_array
            [153] => filter_var_array
            [154] => filter_list
            [155] => filter_has_var
            [156] => filter_id
            [157] => ftp_connect
            [158] => ftp_login
            [159] => ftp_pwd
            [160] => ftp_cdup
            [161] => ftp_chdir
            [162] => ftp_exec
            [163] => ftp_raw
            [164] => ftp_mkdir
            [165] => ftp_rmdir
            [166] => ftp_chmod
            [167] => ftp_alloc
            [168] => ftp_nlist
            [169] => ftp_rawlist
            [170] => ftp_systype
            [171] => ftp_pasv
            [172] => ftp_get
            [173] => ftp_fget
            [174] => ftp_put
            [175] => ftp_fput
            [176] => ftp_size
            [177] => ftp_mdtm
            [178] => ftp_rename
            [179] => ftp_delete
            [180] => ftp_site
            [181] => ftp_close
            [182] => ftp_set_option
            [183] => ftp_get_option
            [184] => ftp_nb_fget
            [185] => ftp_nb_get
            [186] => ftp_nb_continue
            [187] => ftp_nb_put
            [188] => ftp_nb_fput
            [189] => ftp_quit
            [190] => hash
            [191] => hash_file
            [192] => hash_hmac
            [193] => hash_hmac_file
            [194] => hash_init
            [195] => hash_update
            [196] => hash_update_stream
            [197] => hash_update_file
            [198] => hash_final
            [199] => hash_algos
            [200] => iconv
            [201] => ob_iconv_handler
            [202] => iconv_get_encoding
            [203] => iconv_set_encoding
            [204] => iconv_strlen
            [205] => iconv_substr
            [206] => iconv_strpos
            [207] => iconv_strrpos
            [208] => iconv_mime_encode
            [209] => iconv_mime_decode
            [210] => iconv_mime_decode_headers
            [211] => json_encode
            [212] => json_decode
            [213] => odbc_autocommit
            [214] => odbc_binmode
            [215] => odbc_close
            [216] => odbc_close_all
            [217] => odbc_columns
            [218] => odbc_commit
            [219] => odbc_connect
            [220] => odbc_cursor
            [221] => odbc_data_source
            [222] => odbc_execute
            [223] => odbc_error
            [224] => odbc_errormsg
            [225] => odbc_exec
            [226] => odbc_fetch_array
            [227] => odbc_fetch_object
            [228] => odbc_fetch_row
            [229] => odbc_fetch_into
            [230] => odbc_field_len
            [231] => odbc_field_scale
            [232] => odbc_field_name
            [233] => odbc_field_type
            [234] => odbc_field_num
            [235] => odbc_free_result
            [236] => odbc_gettypeinfo
            [237] => odbc_longreadlen
            [238] => odbc_next_result
            [239] => odbc_num_fields
            [240] => odbc_num_rows
            [241] => odbc_pconnect
            [242] => odbc_prepare
            [243] => odbc_result
            [244] => odbc_resul