PHP操作数组的一些函数整理介绍_php技巧
在数组中搜索一个特定值,如果找到返回TRUE否则返回FALSE
boolean in_array(mixed needle,array haystack[,boolean strict])
在数组中找到一个指定的健,如果找到返回TRUE否则返回FALSE
boolean array_eky_exists(mixed key,array array)
在数组中搜索一个特定值,如果找到返回TRUE否则返回FALSE
boolean array_search(mixed needle,array haystack[,boolean strict])
获取数组所有键组成的新数组
array array_keys(array array[,mixed search_value])
获取数组所有值组成的新数组
array array_values(array array)
确定数组大小
integer count(array array[,int mode])
integer sizeof(array array[,int mode])
统计数组元素出现频率
array array_count_values(array array)
删除数组中重复的值,返回一个由唯一值组成的数组
array array_unique(array array)
逆置数组元素顺序,preserve_key如果为TRUE则数组键值顺序不变
array array_reverse(array array[,boolean preserve_key])
置换数组键和值
array array_flip(array array)
数组顺序排序,sort_flags参数可选,默认行为
SORT_NUMBERIC,按数值排序,对整数或浮点数排序很有用
SORT_REGULAR,按照ASCII值排序
SORT_STRING,按接近人所认识的正确顺序排序
asort函数键值顺序不变
void sort(array array[,int sort_flags])
void asort(array array[,int sort_flags])
数组逆序排序,sort_flags参数可选,默认行为
SORT_NUMBERIC,按数值排序,对整数或浮点数排序很有用
SORT_REGULAR,按照ASCII值排序
SORT_STRING,按接近人所认识的正确顺序排序
arsort函数键值顺序不变
void rsort(array array[,int sort_flags])
void arsort(array array[,int sort_flags])
数组自然排序
void natsort(array array)
不区分大小写的自然排序
void natcasesort(array array)
健键值对数组排序
boolean ksort(array array[,int sort_flags])
健键值对数组逆序排序
boolean krsort(array array[,int sort_flags])
根据用户自定义顺序排序
void usort(array array,callback function_name)
将数组合并到一起,返回一个联合的数组。array_merge后面覆盖前面,array_merge_recursive合并在一起
array array_merge(array array1[array array2……])//一个以上
array array_merge_recursive(array array1,array array2[,array ……])//两个以上
键和值组成新的数组
array array_combine(array key,array value)
返回数组一部分,从健offset开始,到offse+length位置结束
array array_slice(array array, int offset [,int length])
删除从offset开始到offset+length结束的所有元素,并以数组的形式返回删除的元素
array array_splice(array, int offset [,int length[,array peplacement]])
求数组的交集,键值为第一个数组中键值
array array_intersect(array array1,array array2[,arrayN……])
求数组的交集包含了键值相等,键值为第一个数组中键值
array array_intersect_assoc(array array1,array array2[,arrayN……])
求数组的差集,第一个数组在其他数组没有的值
array array_diff(array array1,array array2[,arrayN……])
求数组的差集,第一个数组在其他数组没有的值包含了键值相等
array array_diffassoc(array array1,array array2[,arrayN……])
返回数组中一个或多个键值
mixed array_rand(array array[,int num_entries])
随即洗牌函数
void shuffle(array input_array)
对数组中的值求和
mixed array_sum(array array);
将数组分解为一个多维数组,它包含了size个元素
array array_chunk(array array, int size [,boolean preserve_keys])

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