迁移时表中的FK不工作

当我在那时为表创建迁移时,它的through-following错误有问题。

照明\数据库\查询异常:sqlstate[hy000]:常规 错误:1005无法创建表 yourwebs_veridocedu . #sql-2c46_8e (errno:150“外键约束格式不正确”)(sql: 更改表 user_role_mappings 添加约束 user_role_mappings_user_id_foreign 外键( user_id ) 参考文献 users ( id )删除时层叠)

用户角色映射表的迁移:

public function up()
    {
        Schema::create('user_role_mappings', function (Blueprint $table) {
            $table->increments('id');

            $table->integer('user_id');
            $table->integer('group_id');
            $table->integer('roleid');
            $table->integer('status');
            $table->integer('createdby');
            $table->integer('modifiedby');
            $table->string('publicguid');
            $table->string('privateguid');
            $table->timestamps();

            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
            $table->foreign('group_id')->references('id')->on('groups')->onDelete('cascade');
        });
    }

角色表迁移:

public function up()
{
    Schema::create('userroles', function (Blueprint $table) {
        $table->increments('id');
        $table->string('rolename');
         $table->integer('status')->default(1);
        $table->integer('createdby')->default(1);
        $table->integer('modifiedby')->default(1);
        $table->string('publicguid');
        $table->string('privateguid');
        $table->timestamps(); 

    });
}

用户表迁移:

    <?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('users', function (Blueprint $table) {
            $table->engine = 'InnoDB';
            $table->increments('id');


            $table->string('name');
            $table->string('email',150)->unique();
            $table->string('password');
            $table->integer('roleid')->unsigned();
            $table->rememberToken();

            /*Common Fields*/
            $table->integer('status');
            $table->integer('createdby');
            $table->integer('modifiedby');
            $table->string('publicguid');
            $table->string('privateguid');
            $table->timestamps();

           /*From other table */
            $table->foreign('roleid') ->references('id')->on('userroles')->onDelete('cascade');

        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */

    public function down()
    {
        Schema::dropIfExists('users');
    }
}

表中的FK不工作,无法迁移。